A340031
Irregular triangle read by rows T(n,k) in which row n lists n blocks, where the m-th block consists of A000041(m-1) copies of the j-th row of triangle A127093, where j = n - m + 1 and 1 <= m <= n.
Original entry on oeis.org
1, 1, 2, 1, 1, 0, 3, 1, 2, 1, 1, 1, 2, 0, 4, 1, 0, 3, 1, 2, 1, 2, 1, 1, 1, 1, 0, 0, 0, 5, 1, 2, 0, 4, 1, 0, 3, 1, 0, 3, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 2, 3, 0, 0, 6, 1, 0, 0, 0, 5, 1, 2, 0, 4, 1, 2, 0, 4, 1, 0, 3, 1, 0, 3, 1, 0, 3, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1
Offset: 1
Triangle begins:
[1];
[1,2], [1];
[1,0,3], [1,2], [1], [1];
[1,2,0,4], [1,0,3], [1,2], [1,2], [1], [1], [1];
[1,0,0,0,5],[1,2,0,4],[1,0,3],[1,0,3],[1,2],[1,2],[1,2],[1],[1],[1],[1],[1];
[...
Written as an irregular tetrahedron the first five slices are:
[1],
-------
[1, 2],
[1],
----------
[1, 0, 3],
[1, 2],
[1],
[1];
-------------
[1, 2, 0, 4],
[1, 0, 3],
[1, 2],
[1, 2],
[1],
[1],
[1];
----------------
[1, 0, 0, 0, 5],
[1, 2, 0, 4],
[1, 0, 3],
[1, 0, 3],
[1, 2],
[1, 2],
[1, 2],
[1],
[1],
[1],
[1],
[1];
.
The following table formed by three zones shows the correspondence between divisors and parts (n = 1..5):
.
|---|---------|-----|-------|---------|-----------|-------------|
| n | | 1 | 2 | 3 | 4 | 5 |
|---|---------|-----|-------|---------|-----------|-------------|
| P | | | | | | |
| A | | | | | | |
| R | | | | | | |
| T | | | | | | 5 |
| I | | | | | | 3 2 |
| T | | | | | 4 | 4 1 |
| I | | | | | 2 2 | 2 2 1 |
| O | | | | 3 | 3 1 | 3 1 1 |
| N | | | 2 | 2 1 | 2 1 1 | 2 1 1 1 |
| S | | 1 | 1 1 | 1 1 1 | 1 1 1 1 | 1 1 1 1 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A181187 | 1 | 3 1 | 6 2 1 | 12 5 2 1 | 20 8 4 2 1 |
| L | | | | |/| | |/|/| | |/|/|/| | |/|/|/|/| |
| I | A066633 | 1 | 2 1 | 4 1 1 | 7 3 1 1 | 12 4 2 1 1 |
| N | | * | * * | * * * | * * * * | * * * * * |
| K | A002260 | 1 | 1 2 | 1 2 3 | 1 2 3 4 | 1 2 3 4 5 |
| | | = | = = | = = = | = = = = | = = = = = |
| | A138785 | 1 | 2 2 | 4 2 3 | 7 6 3 4 | 12 8 6 4 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A127093 | 1 | 1 2 | 1 0 3 | 1 2 0 4 | 1 0 0 0 5 |
| |---------|-----|-------|---------|-----------|-------------|
| | A127093 | | 1 | 1 2 | 1 0 3 | 1 2 0 4 |
| |---------|-----|-------|---------|-----------|-------------|
| D | A127093 | | | 1 | 1 2 | 1 0 3 |
| I | A127093 | | | 1 | 1 2 | 1 0 3 |
| V |---------|-----|-------|---------|-----------|-------------|
| I | A127093 | | | | 1 | 1 2 |
| S | A127093 | | | | 1 | 1 2 |
| O | A127093 | | | | 1 | 1 2 |
| R |---------|-----|-------|---------|-----------|-------------|
| S | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
The table is essentially the same table of A338156 but here, in the lower zone, every row is A127093 instead of A027750.
.
Cf.
A000070,
A000041,
A002260,
A026792,
A027750,
A058399,
A066633,
A127093,
A135010,
A138121,
A138785,
A176206,
A181187,
A182703,
A207031,
A207383,
A211992,
A221529,
A221530,
A221531,
A221649,
A221650,
A237593,
A245095,
A302246,
A302247,
A336811,
A337209,
A339106,
A339258,
A339278,
A339304,
A340011,
A340032,
A340035,
A340061.
A340011
Irregular triangle read by rows T(n,k) in which row n lists n blocks, where the m-th block consists of the j-th row of triangle A127093 but with every term multiplied by A000041(m-1), where j = n - m + 1 and 1 <= m <= n.
Original entry on oeis.org
1, 1, 2, 1, 1, 0, 3, 1, 2, 2, 1, 2, 0, 4, 1, 0, 3, 2, 4, 3, 1, 0, 0, 0, 5, 1, 2, 0, 4, 2, 0, 6, 3, 6, 5, 1, 2, 3, 0, 0, 6, 1, 0, 0, 0, 5, 2, 4, 0, 8, 3, 0, 9, 5, 10, 7, 1, 0, 0, 0, 0, 0, 7, 1, 2, 3, 0, 0, 6, 2, 0, 0, 0, 10, 3, 6, 0, 12, 5, 0, 15, 7, 14, 11, 1, 2, 0, 4, 0, 0, 0, 8
Offset: 1
Triangle begins:
[1];
[1, 2], [1];
[1, 0, 3], [1, 2], [2];
[1, 2, 0, 4], [1, 0, 3], [2, 4], [3];
[1, 0, 0, 0, 5], [1, 2, 0, 4], [2, 0, 6], [3, 6], [5];
[...
Row sums give A066186.
Written as an irregular tetrahedron the first five slices are:
--
1;
-----
1, 2,
1;
--------
1, 0, 3,
1, 2,
2;
-----------
1, 2, 0, 4,
1, 0, 3,
2, 4,
3;
--------------
1, 0, 0, 0, 5,
1, 2, 0, 4,
2, 0, 6,
3, 6,
5;
--------------
Row sums give A339106.
The following table formed by four zones shows the correspondence between divisor and parts (n = 1..5):
.
|---|---------|-----|-------|---------|-----------|-------------|
| n | | 1 | 2 | 3 | 4 | 5 |
|---|---------|-----|-------|---------|-----------|-------------|
| P | | | | | | |
| A | | | | | | |
| R | | | | | | |
| T | | | | | | 5 |
| I | | | | | | 3 2 |
| T | | | | | 4 | 4 1 |
| I | | | | | 2 2 | 2 2 1 |
| O | | | | 3 | 3 1 | 3 1 1 |
| N | | | 2 | 2 1 | 2 1 1 | 2 1 1 1 |
| S | | 1 | 1 1 | 1 1 1 | 1 1 1 1 | 1 1 1 1 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A181187 | 1 | 3 1 | 6 2 1 | 12 5 2 1 | 20 8 4 2 1 |
| L | | | | |/| | |/|/| | |/|/|/| | |/|/|/|/| |
| I | A066633 | 1 | 2 1 | 4 1 1 | 7 3 1 1 | 12 4 2 1 1 |
| N | | * | * * | * * * | * * * * | * * * * * |
| K | A002260 | 1 | 1 2 | 1 2 3 | 1 2 3 4 | 1 2 3 4 5 |
| | | = | = = | = = = | = = = = | = = = = = |
| | A138785 | 1 | 2 2 | 4 2 3 | 7 6 3 4 | 12 8 6 4 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A127093 | 1 | 1 2 | 1 0 3 | 1 2 0 4 | 1 0 0 0 5 |
| |---------|-----|-------|---------|-----------|-------------|
| | A127093 | | 1 | 1 2 | 1 0 3 | 1 2 0 4 |
| |---------|-----|-------|---------|-----------|-------------|
| D | A127093 | | | 1 | 1 2 | 1 0 3 |
| I | A127093 | | | 1 | 1 2 | 1 0 3 |
| V |---------|-----|-------|---------|-----------|-------------|
| I | A127093 | | | | 1 | 1 2 |
| S | A127093 | | | | 1 | 1 2 |
| O | A127093 | | | | 1 | 1 2 |
| R |---------|-----|-------|---------|-----------|-------------|
| S | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A127093 | 1 | 1 2 | 1 0 3 | 1 2 0 4 | 1 0 0 0 5 |
| C | A127093 | | 1 | 1 2 | 1 0 3 | 1 2 0 4 |
| O | - | | | 2 | 2 4 | 2 0 6 |
| N | - | | | | 3 | 3 6 |
| D | - | | | | | 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
This lower zone of the table is a condensed version of the "divisors" zone.
Cf.
A000070,
A000041,
A002260,
A026792,
A027750,
A058399,
A066633,
A127093,
A135010,
A138121,
A138785,
A176206,
A181187,
A182703,
A207031,
A207383,
A211992,
A221529,
A221530,
A221531,
A221649,
A221650,
A237593,
A245095,
A302246,
A302247,
A336811,
A336812,
A337209,
A338156,
A339106,
A339258,
A339278,
A339304,
A340031,
A340032,
A340035,
A340061.
A340032
Irregular triangle read by rows T(n,k) in which row n lists n blocks, where the m-th block consists of A000041(n-m) copies of the row m of triangle A127093, with 1 <= m <= n.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 1, 2, 1, 0, 3, 1, 1, 1, 1, 2, 1, 2, 1, 0, 3, 1, 2, 0, 4, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 0, 3, 1, 0, 3, 1, 2, 0, 4, 1, 0, 0, 0, 5, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 0, 3, 1, 0, 3, 1, 0, 3, 1, 2, 0, 4, 1, 2, 0, 4, 1, 0, 0, 0, 5, 1, 2, 3, 0, 0, 6
Offset: 1
Triangle begins:
1;
1, 1, 2;
1, 1, 1, 2, 1, 0, 3;
1, 1, 1, 1, 2, 1, 2, 1, 0, 3, 1, 2, 0, 4;
1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 0, 3, 1, 0, 3, 1, 2, 0, 4, 1, 0, 0, 0, 5;
...
Written as an irregular tetrahedron the first five slices are:
1;
--
1,
1, 2;
-----
1,
1,
1, 2,
1, 0, 3;
--------
1,
1,
1,
1, 2,
1, 2,
1, 0, 3,
1, 2, 0, 4;
-----------
1,
1,
1,
1,
1,
1, 2,
1, 2,
1, 2,
1, 0, 3,
1, 0, 3,
1, 2, 0, 4,
1, 0, 0, 0, 5;
--------------
...
The slices of the tetrahedron appear in the upper zone of the following table (formed by three zones) which shows the correspondence between divisors and parts (n = 1..5):
.
|---|---------|-----|-------|---------|-----------|-------------|
| n | | 1 | 2 | 3 | 4 | 5 |
|---|---------|-----|-------|---------|-----------|-------------|
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| | A127093 | | | | | 1 |
| D | A127093 | | | | | 1 |
| I |---------|-----|-------|---------|-----------|-------------|
| V | A127093 | | | | 1 | 1 2 |
| I | A127093 | | | | 1 | 1 2 |
| S | A127093 | | | | 1 | 1 2 |
| O |---------|-----|-------|---------|-----------|-------------|
| R | A127093 | | | 1 | 1 2 | 1 0 3 |
| S | A127093 | | | 1 | 1 2 | 1 0 3 |
| |---------|-----|-------|---------|-----------|-------------|
| | A127093 | | 1 | 1 2 | 1 0 3 | 1 2 0 4 |
| |---------|-----|-------|---------|-----------|-------------|
| | A127093 | 1 | 1 2 | 1 0 3 | 1 2 0 4 | 1 0 0 0 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A138785 | 1 | 2 2 | 4 2 3 | 7 6 3 4 | 12 8 6 4 5 |
| | | = | = = | = = = | = = = = | = = = = = |
| L | A002260 | 1 | 1 2 | 1 2 3 | 1 2 3 4 | 1 2 3 4 5 |
| I | | * | * * | * * * | * * * * | * * * * * |
| N | A066633 | 1 | 2 1 | 4 1 1 | 7 3 1 1 | 12 4 2 1 1 |
| K | | | | |\| | |\|\| | |\|\|\| | |\|\|\|\| |
| | A181187 | 1 | 3 1 | 6 2 1 | 12 5 2 1 | 20 8 4 2 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| P | | 1 | 1 1 | 1 1 1 | 1 1 1 1 | 1 1 1 1 1 |
| A | | | 2 | 2 1 | 2 1 1 | 2 1 1 1 |
| R | | | | 3 | 3 1 | 3 1 1 |
| T | | | | | 2 2 | 2 2 1 |
| I | | | | | 4 | 4 1 |
| T | | | | | | 3 2 |
| I | | | | | | 5 |
| O | | | | | | |
| N | | | | | | |
| S | | | | | | |
|---|---------|-----|-------|---------|-----------|-------------|
.
The table is essentially the same table of A340035 but here, in the upper zone, every row is A127093 instead of A027750.
Also the above table is the table of A340031 upside down.
Cf.
A000070,
A000041,
A002260,
A026792,
A027750,
A058399,
A066633,
A127093,
A135010,
A138121,
A138785,
A176206,
A181187,
A182703,
A207031,
A207383,
A211992,
A221529,
A221530,
A221531,
A245095,
A221649,
A221650,
A237593,
A302246,
A302247,
A336811,
A337209,
A338156,
A339106,
A339258,
A339278,
A339304,
A340031,
A340061.
A340423
Irregular triangle read by rows T(n,k) in which row n has length A000041(n-1) and every column k is A024916, n >= 1, k >= 1.
Original entry on oeis.org
1, 4, 8, 1, 15, 4, 1, 21, 8, 4, 1, 1, 33, 15, 8, 4, 4, 1, 1, 41, 21, 15, 8, 8, 4, 4, 1, 1, 1, 1, 56, 33, 21, 15, 15, 8, 8, 4, 4, 4, 4, 1, 1, 1, 1, 69, 41, 33, 21, 21, 15, 15, 8, 8, 8, 8, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 87, 56, 41, 33, 33, 21, 21, 15, 15, 15, 15, 8, 8, 8, 8
Offset: 1
Triangle begins:
1;
4;
8, 1;
15, 4, 1;
21, 8, 4, 1, 1;
33, 15, 8, 4, 4, 1, 1;
41, 21, 15, 8, 8, 4, 4, 1, 1, 1, 1;
56, 33, 21, 15, 15, 8, 8, 4, 4, 4, 4, 1, 1, 1, 1;
69, 41, 33, 21, 21, 15, 15, 8, 8, 8, 8, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1;
...
For n = 9 the length of row 9 is A000041(9-1) = 22.
From _Omar E. Pol_, Jan 08 2022: (Start)
For n = 9 the lateral view and top view of the tower described in A221529 look like as shown below:
_
22 1 | |
21 1 | |
20 1 | |
19 1 | |
18 1 | |
17 1 | |
16 1 |_|_
15 4 | |
14 4 | |
13 4 | |
12 4 |_ _|_
11 8 | | |
10 8 | | |
9 8 | | |
8 8 |_ _|_|_
7 15 | | |
6 15 |_ _ _| |_
5 21 | | |
4 21 |_ _ _|_ _|_
3 33 |_ _ _ _| | |_
2 41 |_ _ _ _|_|_ _|_ _
1 69 |_ _ _ _ _|_ _|_ _|
.
Level Row 9 Lateral view
k T(9,k) of the tower
.
_ _ _ _ _ _ _ _ _
|_| | | | | | | |
|_ _|_| | | | | |
|_ _| _|_| | | |
|_ _ _| _|_| |
|_ _ _| _| _ _|
|_ _ _ _| |
|_ _ _ _| _ _|
| |
|_ _ _ _ _|
.
Top view
of the tower
.
For n = 9 and k = 1 there are 69 cubic cells in the level 1 starting from the base of the tower, so T(9,1) = 69.
For n = 9 and k = 22 there is only one cubic cell in the level 22 (the top) of the tower, so T(9,22) = 1.
The volume of the tower (also the total number of cubic cells) represents the 9th term of the convolution of A000203 and A000041 hence it's equal to A066186(9) = 270, equaling the sum of the 9th row of triangle. (End)
The length of the m-th block in row n is
A187219(m), m >= 1.
Cf.
A000203,
A024916,
A196020,
A221529,
A236104,
A235791,
A237270,
A237271,
A237593,
A339278,
A262626,
A336811,
A338156,
A340035,
A341149,
A346533,
A350333.
-
f(n) = numbpart(n-1);
T(n, k) = {if (k > f(n), error("invalid k")); if (k==1, return (n)); my(s=0); while (k <= f(n-1), s++; n--; ); 1+s; } \\ A336811
g(n) = sum(k=1, n, n\k*k); \\ A024916
row(n) = vector(f(n), k, g(T(n,k))); \\ Michel Marcus, Jan 22 2022
A340584
Irregular triangle read by rows T(n,k) in which row n lists sigma(n) + sigma(n-1) together with the first n - 2 terms of A000203 in reverse order, with T(1,1) = 1, n >= 1.
Original entry on oeis.org
1, 4, 7, 1, 11, 3, 1, 13, 4, 3, 1, 18, 7, 4, 3, 1, 20, 6, 7, 4, 3, 1, 23, 12, 6, 7, 4, 3, 1, 28, 8, 12, 6, 7, 4, 3, 1, 31, 15, 8, 12, 6, 7, 4, 3, 1, 30, 13, 15, 8, 12, 6, 7, 4, 3, 1, 40, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1, 42, 12, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1, 38, 28, 12, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1
Offset: 1
Triangle begins:
1;
4;
7, 1;
11, 3, 1;
13, 4, 3, 1;
18, 7, 4, 3, 1;
20, 6, 7, 4, 3, 1;
23, 12, 6, 7, 4, 3, 1;
28, 8, 12, 6, 7, 4, 3, 1;
31, 15, 8, 12, 6, 7, 4, 3, 1;
30, 13, 15, 8, 12, 6, 7, 4, 3, 1;
40, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1;
42, 12, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1;
38, 28, 12, 18, 13, 15, 8, 12, 6, 7, 4, 3, 1;
...
For n = 7, sigma(7) = 1 + 7 = 8 and sigma(6) = 1 + 2 + 3 + 6 = 12, and 8 + 12 = 20, so the first term of row 7 is T(7,1) = 20. The other terms in row 7 are the first five terms of A000203 in reverse order, that is [6, 7, 4, 3, 1] so the 7th row of the triangle is [20, 6, 7, 4, 3, 1].
From _Omar E. Pol_, Jul 11 2021: (Start)
For n = 7 we can see below the top view and the lateral view of the pyramid described in A245092 (with seven levels) and the top view and the lateral view of the tower described in A221529 (with 11 levels).
_
| |
| |
| |
_ |_|_
|_|_ | |
|_ _|_ |_ _|_
|_ _|_|_ | | |
|_ _ _| |_ |_ _|_|_
|_ _ _|_ _|_ |_ _ _| |_
|_ _ _ _| | |_ |_ _ _|_ _|_ _
|_ _ _ _|_|_ _| |_ _ _ _|_|_ _|
.
Figure 1. Figure 2.
Lateral view Lateral view
of the pyramid. of the tower.
.
. _ _ _ _ _ _ _ _ _ _ _ _ _ _
|_| | | | | | | |_| | | | | |
|_ _|_| | | | | |_ _|_| | | |
|_ _| _|_| | | |_ _| _|_| |
|_ _ _| _|_| |_ _ _| _ _|
|_ _ _| _| |_ _ _| _|
|_ _ _ _| | |
|_ _ _ _| |_ _ _ _|
.
Figure 3. Figure 4.
Top view Top view
of the pyramid. of the tower.
.
Both polycubes have the same base which has an area equal to A024916(7) = 41 equaling the sum of the 7th row of triangle.
Note that in the top view of the tower the symmetric representation of sigma(6) and the symmetric representation of sigma(7) appear unified in the level 1 of the structure as shown above in the figure 4 (that is due to the first two partition numbers A000041 are [1, 1]), so T(7,1) = sigma(7) + sigma(6) = 8 + 12 = 20. (End)
The length of row n is
A028310(n-1).
Column 1 gives 1 together with
A092403.
Cf.
A175254 (volume of the pyramid).
-
Table[If[n <= 2, {Total@ #}, Prepend[#2, Total@ #1] & @@ TakeDrop[#, 2]] &@ DivisorSigma[1, Range[n, 1, -1]], {n, 14}] // Flatten (* Michael De Vlieger, Jan 13 2021 *)
A340057
Irregular triangle read by rows T(n,k) in which row n lists n blocks, where the block m consists of the divisors of m multiplied by A000041(n-m), with 1 <= m <= n.
Original entry on oeis.org
1, 1, 1, 2, 2, 1, 2, 1, 3, 3, 2, 4, 1, 3, 1, 2, 4, 5, 3, 6, 2, 6, 1, 2, 4, 1, 5, 7, 5, 10, 3, 9, 2, 4, 8, 1, 5, 1, 2, 3, 6, 11, 7, 14, 5, 15, 3, 6, 12, 2, 10, 1, 2, 3, 6, 1, 7, 15, 11, 22, 7, 21, 5, 10, 20, 3, 15, 2, 4, 6, 12, 1, 7, 1, 2, 4, 8, 22, 15, 30, 11, 33, 7, 14, 28, 5, 25
Offset: 1
Triangle begins:
[1];
[1], [1, 2];
[2], [1, 2], [1, 3];
[3], [2, 4], [1, 3], [1, 2, 4];
[5], [3, 6], [2, 6], [1, 2, 4], [1, 5];
[7], [5, 10], [3, 9], [2, 4, 8], [1, 5], [1, 2, 3, 6];
[11], [7, 14], [5, 15], [3, 6, 12], [2, 10], [1, 2, 3, 6], [1, 7];
...
Row sums gives A066186.
Written as a tetrahedrons the first five slices are:
--
1;
--
1,
1, 2;
-----
2,
1, 2,
1, 3;
-----
3,
2, 4,
1, 3,
1, 2, 4;
--------
5,
3, 6,
2, 6,
1, 2, 4,
1, 5;
--------
Row sums give A221529.
The slices of the tetrahedron appear in the upper zone of the following table (formed by four zones) which shows the correspondence between divisors and parts (n = 1..5):
.
|---|---------|-----|-------|---------|-----------|-------------|
| n | | 1 | 2 | 3 | 4 | 5 |
|---|---------|-----|-------|---------|-----------|-------------|
| | - | | | | | 5 |
| C | - | | | | 3 | 3 6 |
| O | - | | | 2 | 2 4 | 2 6 |
| N | A027750 | | 1 | 1 2 | 1 3 | 1 2 4 |
| D | A027750 | 1 | 1 2 | 1 3 | 1 2 4 | 1 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A027750 | | | | | 1 |
| | A027750 | | | | | 1 |
| | A027750 | | | | | 1 |
| | A027750 | | | | | 1 |
| D | A027750 | | | | | 1 |
| I |---------|-----|-------|---------|-----------|-------------|
| V | A027750 | | | | 1 | 1 2 |
| I | A027750 | | | | 1 | 1 2 |
| S | A027750 | | | | 1 | 1 2 |
| O |---------|-----|-------|---------|-----------|-------------|
| R | A027750 | | | 1 | 1 2 | 1 3 |
| S | A027750 | | | 1 | 1 2 | 1 3 |
| |---------|-----|-------|---------|-----------|-------------|
| | A027750 | | 1 | 1 2 | 1 3 | 1 2 4 |
| |---------|-----|-------|---------|-----------|-------------|
| | A027750 | 1 | 1 2 | 1 3 | 1 2 4 | 1 5 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| | A138785 | 1 | 2 2 | 4 2 3 | 7 6 3 4 | 12 8 6 4 5 |
| | | = | = = | = = = | = = = = | = = = = = |
| L | A002260 | 1 | 1 2 | 1 2 3 | 1 2 3 4 | 1 2 3 4 5 |
| I | | * | * * | * * * | * * * * | * * * * * |
| N | A066633 | 1 | 2 1 | 4 1 1 | 7 3 1 1 | 12 4 2 1 1 |
| K | | | | |\| | |\|\| | |\|\|\| | |\|\|\|\| |
| | A181187 | 1 | 3 1 | 6 2 1 | 12 5 2 1 | 20 8 4 2 1 |
|---|---------|-----|-------|---------|-----------|-------------|
.
|---|---------|-----|-------|---------|-----------|-------------|
| P | | 1 | 1 1 | 1 1 1 | 1 1 1 1 | 1 1 1 1 1 |
| A | | | 2 | 2 1 | 2 1 1 | 2 1 1 1 |
| R | | | | 3 | 3 1 | 3 1 1 |
| T | | | | | 2 2 | 2 2 1 |
| I | | | | | 4 | 4 1 |
| T | | | | | | 3 2 |
| I | | | | | | 5 |
| O | | | | | | |
| N | | | | | | |
| S | | | | | | |
|---|---------|-----|-------|---------|-----------|-------------|
.
The upper zone is a condensed version of the "divisors" zone.
The above table is the table of A340056 upside down.
Cf.
A000041,
A002260,
A027750,
A066186,
A066633,
A127093,
A135010,
A138121,
A138785,
A176206,
A181187,
A182703,
A207031,
A207383,
A221529,
A221530,
A221531,
A236104,
A237593,
A245092,
A245095,
A221650,
A302246,
A302247,
A336811,
A336812,
A337209,
A338156,
A339106,
A339258,
A339278,
A339304,
A340011,
A340031,
A340032,
A340056,
A340057,
A340061.
A346533
Irregular triangle read by rows in which row n lists the first n - 2 terms of A000203 together with the sum of A000203(n-1) and A000203(n), with a(1) = 1.
Original entry on oeis.org
1, 4, 1, 7, 1, 3, 11, 1, 3, 4, 13, 1, 3, 4, 7, 18, 1, 3, 4, 7, 6, 20, 1, 3, 4, 7, 6, 12, 23, 1, 3, 4, 7, 6, 12, 8, 28, 1, 3, 4, 7, 6, 12, 8, 15, 31, 1, 3, 4, 7, 6, 12, 8, 15, 13, 30, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 40, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 42, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 28, 38
Offset: 1
Triangle begins:
1;
4;
1, 7;
1, 3, 11;
1, 3, 4, 13;
1, 3, 4, 7, 18;
1, 3, 4, 7, 6, 20;
1, 3, 4, 7, 6, 12, 23;
1, 3, 4, 7, 6, 12, 8, 28;
1, 3, 4, 7, 6, 12, 8, 15, 31;
1, 3, 4, 7, 6, 12, 8, 15, 13, 30;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 40;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 42;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 28, 38;
...
For n = 7, sigma(7) = 1 + 7 = 8 and sigma(6) = 1 + 2 + 3 + 6 = 12, and 8 + 12 = 20, so the last term of row 7 is T(7,6) = 20. The other terms in row 7 are the first five terms of A000203, so the 7th row of the triangle is [1, 3, 4, 7, 6, 20].
For n = 7 we can see below the top view and the lateral view of the pyramid described in A245092 (with seven levels) and the top view and the lateral view of the tower described in A221529 (with 11 levels).
_
| |
| |
| |
_ |_|_
|_|_ | |
|_ _|_ |_ _|_
|_ _|_|_ | | |
|_ _ _| |_ |_ _|_|_
|_ _ _|_ _|_ |_ _ _| |_
|_ _ _ _| | |_ |_ _ _|_ _|_ _
|_ _ _ _|_|_ _| |_ _ _ _|_|_ _|
.
Figure 1. Figure 2.
Lateral view Lateral view
of the pyramid. of the tower.
.
. _ _ _ _ _ _ _ _ _ _ _ _ _ _
|_| | | | | | | |_| | | | | |
|_ _|_| | | | | |_ _|_| | | |
|_ _| _|_| | | |_ _| _|_| |
|_ _ _| _|_| |_ _ _| _ _|
|_ _ _| _| |_ _ _| _|
|_ _ _ _| | |
|_ _ _ _| |_ _ _ _|
.
Figure 3. Figure 4.
Top view Top view
of the pyramid. of the tower.
.
Both polycubes have the same base which has an area equal to A024916(7) = 41 equaling the sum of the 7th row of triangle.
Note that in the top view of the tower the symmetric representation of sigma(6) and the symmetric representation of sigma(7) appear unified in the level 1 of the structure as shown above in the figure 4 (that is due the first two partition numbers A000041 are [1, 1]), so T(7,6) = sigma(7) + sigma(6) = 8 + 12 = 20.
.
Illustration of initial terms:
Row 1 Row 2 Row 3 Row 4 Row 5 Row 6
.
1 4 1 7 1 3 11 1 3 4 13 1 3 4 7 18
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
|_| | | |_| | |_| | | |_| | | | |_| | | | |
|_ _| | _| |_ _| | |_ _|_| | |_ _|_| | |
|_ _| | _| |_ _| _ _| |_ _| _| |
|_ _ _| | | |_ _ _| _|
|_ _ _| | _|
|_ _ _ _|
.
The length of row n is
A028310(n-1).
Cf.
A175254 (volume of the pyramid).
Cf.
A000041,
A221529,
A237270,
A237593,
A245092,
A245093 (similar),
A336811,
A336812,
A338156,
A339106,
A340035.
-
A346533row[n_]:=If[n==1,{1},Join[DivisorSigma[1,Range[n-2]],{Total[DivisorSigma[1,{n-1,n}]]}]];Array[A346533row,15] (* Paolo Xausa, Oct 23 2023 *)
A340527
Triangle read by rows: T(n,k) = A024916(n-k+1)*A000041(k-1), 1 <= k <= n.
Original entry on oeis.org
1, 4, 1, 8, 4, 2, 15, 8, 8, 3, 21, 15, 16, 12, 5, 33, 21, 30, 24, 20, 7, 41, 33, 42, 45, 40, 28, 11, 56, 41, 66, 63, 75, 56, 44, 15, 69, 56, 82, 99, 105, 105, 88, 60, 22, 87, 69, 112, 123, 165, 147, 165, 120, 88, 30, 99, 87, 138, 168, 205, 231, 231, 225, 176, 120, 42, 127, 99, 174
Offset: 1
Triangle begins:
1;
4, 1;
8, 4, 2;
15, 8, 8, 3;
21, 15, 16, 12, 5;
33, 21, 30, 24, 20, 7;
41, 33, 42, 45, 40, 28, 11;
56, 41, 66, 63, 75, 56, 44, 15;
69, 56, 82, 99, 105, 105, 88, 60, 22;
87, 69, 112, 123, 165, 147, 165, 120, 88, 30;
99, 87, 138, 168, 205, 231, 231, 225, 176, 120, 42;
...
For n = 6 the calculation of every term of row 6 is as follows:
--------------------------
k A000041 T(6,k)
1 1 * 33 = 33
2 1 * 21 = 21
3 2 * 15 = 30
4 3 * 8 = 24
5 5 * 4 = 20
6 7 * 1 = 7
. A024916
--------------------------
The sum of row 6 is 33 + 21 + 30 + 24 + 20 + 7 = 135, equaling A182738(6).
Cf.
A000070,
A066186,
A176206,
A221529,
A221531,
A237270,
A237593,
A336811,
A336812,
A338156,
A339106,
A340035,
A340424,
A340425,
A340426,
A340524,
A340526.
A346741
Irregular triangle read by rows which is constructed in row n replacing the first A000070(n-1) terms of A336811 with their divisors.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 2, 1, 3, 1, 1, 1, 2, 1, 3, 1, 1, 2, 4, 1, 2, 1, 1, 1, 2, 1, 3, 1, 1, 2, 4, 1, 2, 1, 1, 5, 1, 3, 1, 2, 1, 1, 1, 1, 2, 1, 3, 1, 1, 2, 4, 1, 2, 1, 1, 5, 1, 3, 1, 2, 1, 1, 1, 2, 3, 6, 1, 2, 4, 1, 3, 1, 2, 1, 2, 1, 1, 1, 7, 1, 5, 1, 2, 4, 1, 3, 1, 3, 1, 2, 1, 2, 1, 1, 1, 1
Offset: 1
Triangle begins:
[1];
[1],[1, 2];
[1],[1, 2],[1, 3],[1];
[1],[1, 2],[1, 3],[1],[1, 2, 4],[1, 2],[1];
[1],[1, 2],[1, 3],[1],[1, 2, 4],[1, 2],[1],[1, 5],[1, 3],[1, 2],[1],[1];
...
Below the table shows the correspondence divisor/part.
|---|-----------------|-----|-------|---------|-----------|-------------|
| n | | 1 | 2 | 3 | 4 | 5 |
|---|-----------------|-----|-------|---------|-----------|-------------|
| P | | | | | | |
| A | | | | | | |
| R | | | | | | |
| T | | | | | | 5 |
| I | | | | | | 3 2 |
| T | | | | | 4 | 4 1 |
| I | | | | | 2 2 | 2 2 1 |
| O | | | | 3 | 3 1 | 3 1 1 |
| N | | | 2 | 2 1 | 2 1 1 | 2 1 1 1 |
| S | | 1 | 1 1 | 1 1 1 | 1 1 1 1 | 1 1 1 1 1 |
----|-----------------|-----|-------|---------|-----------|-------------|
.
|---|-----------------|-----|-------|---------|-----------|-------------|
| | A181187 | 1 | 3 1 | 6 2 1 | 12 5 2 1 | 20 8 4 2 1 |
| L | | | | |/| | |/|/| | |/|/|/| | |/|/|/|/| |
| I | A066633 | 1 | 2 1 | 4 1 1 | 7 3 1 1 | 12 4 2 1 1 |
| N | | * | * * | * * * | * * * * | * * * * * |
| K | A002260 | 1 | 1 2 | 1 2 3 | 1 2 3 4 | 1 2 3 4 5 |
| | | = | = = | = = = | = = = = | = = = = = |
| | A138785 | 1 | 2 2 | 4 2 3 | 7 6 3 4 | 12 8 6 4 5 |
|---|-----------------|-----|-------|---------|-----------|-------------|
.
. |-------|
. |Section|
|---|-------|---------|-----|-------|---------|-----------|-------------|
| | 1 | A000012 | 1 | 1 | 1 | 1 | 1 |
| |-------|---------|-----|-------|---------|-----------|-------------|
| | 2 | A000034 | | 1 2 | 1 2 | 1 2 | 1 2 |
| |-------|---------|-----|-------|---------|-----------|-------------|
| D | 3 | A010684 | | | 1 3 | 1 3 | 1 3 |
| I | | A000012 | | | 1 | 1 | 1 |
| V |-------|---------|-----|-------|---------|-----------|-------------|
| I | 4 | A069705 | | | | 1 2 4 | 1 2 4 |
| S | | A000034 | | | | 1 2 | 1 2 |
| O | | A000012 | | | | 1 | 1 |
| R |-------|---------|-----|-------|---------|-----------|-------------|
| S | 5 | A010686 | | | | | 1 5 |
| | | A010684 | | | | | 1 3 |
| | | A000034 | | | | | 1 2 |
| | | A000012 | | | | | 1 |
| | | A000012 | | | | | 1 |
|---|-------|---------|-----|-------|---------|-----------|-------------|
.
In the above table both the zone of partitions and the "Link" zone are the same zones as in the table of the example section of A338156, but here in the lower zone the divisors are ordered in accordance with the sections of the set of partitions of n.
The number of rows in the j-th section of the lower zone is equal to A000041(j-1).
The divisors of the j-th section are also the parts of the j-th section of the set of partitions of n.
The product of row n is
A007870(n).
Row n lists the first n rows of
A336812.
The number of parts k in row n is
A066633(n,k).
The sum of all parts k in row n is
A138785(n,k).
The number of parts >= k in row n is
A181187(n,k).
The sum of all parts >= k in row n is
A206561(n,k).
The number of parts <= k in row n is
A210947(n,k).
The sum of all parts <= k in row n is
A210948(n,k).
Cf.
A000012,
A000034,
A000041,
A000070,
A002260,
A010684,
A010686,
A027750,
A066633,
A069705,
A135010,
A138785,
A181187,
A221529,
A221649,
A237593,
A302246,
A302247,
A336811,
A340011,
A340031,
A340032,
A340035,
A340056,
A340057.
A346530
a(n) is the number of faces of the polycube called "tower" described in A221529 where n is the longest side of its base.
Original entry on oeis.org
6, 6, 11, 14, 20, 27, 31, 38, 42, 51, 59
Offset: 1
For n = 1 the tower is a cube, and a cube has 6 faces, so a(1) = 6.
Comments