A066186
Sum of all parts of all partitions of n.
Original entry on oeis.org
0, 1, 4, 9, 20, 35, 66, 105, 176, 270, 420, 616, 924, 1313, 1890, 2640, 3696, 5049, 6930, 9310, 12540, 16632, 22044, 28865, 37800, 48950, 63336, 81270, 104104, 132385, 168120, 212102, 267168, 334719, 418540, 520905, 647172, 800569, 988570, 1216215, 1493520
Offset: 0
a(3)=9 because the partitions of 3 are: 3, 2+1 and 1+1+1; and (3) + (2+1) + (1+1+1) = 9.
a(4)=20 because A000041(4)=5 and 4*5=20.
- Vincenzo Librandi, Table of n, a(n) for n = 0..1000
- F. G. Garvan, Higher-order spt functions, Adv. Math. 228 (2011), no. 1, 241-265, alternate copy. - From _N. J. A. Sloane_, Jan 02 2013
- F. G. Garvan, Higher-order spt functions, arXiv:1008.1207 [math.NT], 2010.
- T. J. Osler, A. Hassen and T. R. Chandrupatia, Surprising connections between partitions and divisors, The College Mathematics Journal, Vol. 38. No. 4, Sep. 2007, 278-287 (see p. 287).
- Omar E. Pol, Illustration of a(10), prism and tower, each polycube contains 420 cubes.
- Omar E. Pol, Illustration of initial terms of A066186 and of A139582 (n>=1)
Row sums of triangles
A138785,
A181187,
A245099,
A337209,
A339106,
A340423,
A340424,
A221529,
A302246,
A338156,
A340035,
A340056,
A340057,
A346741. -
Omar E. Pol, Aug 02 2021
-
a066186 = sum . concat . ps 1 where
ps _ 0 = [[]]
ps i j = [t:ts | t <- [i..j], ts <- ps t (j - t)]
-- Reinhard Zumkeller, Jul 13 2013
-
with(combinat): a:= n-> n*numbpart(n): seq(a(n), n=0..50); # Zerinvary Lajos, Apr 25 2007
-
PartitionsP[ Range[0, 60] ] * Range[0, 60]
-
a(n)=numbpart(n)*n \\ Charles R Greathouse IV, Mar 10 2012
-
from sympy import npartitions
def A066186(n): return n*npartitions(n) # Chai Wah Wu, Oct 22 2023
-
[n*Partitions(n).cardinality() for n in range(41)] # Peter Luschny, Jul 29 2014
A221529
Triangle read by rows: T(n,k) = A000203(k)*A000041(n-k), 1 <= k <= n.
Original entry on oeis.org
1, 1, 3, 2, 3, 4, 3, 6, 4, 7, 5, 9, 8, 7, 6, 7, 15, 12, 14, 6, 12, 11, 21, 20, 21, 12, 12, 8, 15, 33, 28, 35, 18, 24, 8, 15, 22, 45, 44, 49, 30, 36, 16, 15, 13, 30, 66, 60, 77, 42, 60, 24, 30, 13, 18, 42, 90, 88, 105, 66, 84, 40, 45, 26, 18, 12, 56, 126, 120, 154, 90, 132, 56, 75, 39, 36, 12, 28
Offset: 1
Triangle begins:
------------------------------------------------------
n| k 1 2 3 4 5 6 7 8 9 10
------------------------------------------------------
1| 1;
2| 1, 3;
3| 2, 3, 4;
4| 3, 6, 4, 7;
5| 5, 9, 8, 7, 6;
6| 7, 15, 12, 14, 6, 12;
7| 11, 21, 20, 21, 12, 12, 8;
8| 15, 33, 28, 35, 18, 24, 8, 15;
9| 22, 45, 44, 49, 30, 36, 16, 15, 13;
10| 30, 66, 60, 77, 42, 60, 24, 30, 13, 18;
...
The sum of row 10 is [30 + 66 + 60 + 77 + 42 + 60 + 24 + 30 + 13 + 18] = A066186(10) = 420.
.
For n = 10 the calculation of the row 10 is as follows:
k A000203 T(10,k)
1 1 * 30 = 30
2 3 * 22 = 66
3 4 * 15 = 60
4 7 * 11 = 77
5 6 * 7 = 42
6 12 * 5 = 60
7 8 * 3 = 24
8 15 * 2 = 30
9 13 * 1 = 13
10 18 * 1 = 18
A000041
.
From _Omar E. Pol_, Jul 13 2021: (Start)
For n = 10 we can see below three views of two associated polycubes called here "prism of partitions" and "tower". Both objects contain the same number of cubes (that property is valid for n >= 1).
_ _ _ _ _ _ _ _ _ _
42 |_ _ _ _ _ |
|_ _ _ _ _|_ |
|_ _ _ _ _ _|_ |
|_ _ _ _ | |
|_ _ _ _|_ _ _|_ |
|_ _ _ _ | |
|_ _ _ _|_ | |
|_ _ _ _ _|_ | |
|_ _ _ | | |
|_ _ _|_ | | |
|_ _ | | | |
|_ _|_ _|_ _|_ _|_ | _
30 |_ _ _ _ _ | | | | 30
|_ _ _ _ _|_ | | | |
|_ _ _ | | | | |
|_ _ _|_ _ _|_ | | | |
|_ _ _ _ | | | | |
|_ _ _ _|_ | | | | |
|_ _ _ | | | | | |
|_ _ _|_ _|_ _|_ | | _|_|
22 |_ _ _ _ | | | | | 22
|_ _ _ _|_ | | | | |
|_ _ _ _ _|_ | | | | |
|_ _ _ | | | | | |
|_ _ _|_ | | | | | |
|_ _ | | | | | | |
|_ _|_ _|_ _|_ | | | _|_ _|
15 |_ _ _ _ | | | | | | | 15
|_ _ _ _|_ | | | | | | |
|_ _ _ | | | | | | | |
|_ _ _|_ _|_ | | | | _|_|_ _|
11 |_ _ _ | | | | | | | | 11
|_ _ _|_ | | | | | | | |
|_ _ | | | | | | | | |
|_ _|_ _|_ | | | | | _| |_ _ _|
7 |_ _ _ | | | | | | | | | 7
|_ _ _|_ | | | | | | _|_ _|_ _ _|
5 |_ _ | | | | | | | | | | | 5
|_ _|_ | | | | | | | _| | |_ _ _ _|
3 |_ _ | | | | | | | | _|_ _|_|_ _ _ _| 3
2 |_ | | | | | | | | | _ _|_ _|_|_ _ _ _ _| 2
1 |_|_|_|_|_|_|_|_|_|_| |_ _|_|_|_ _ _ _ _ _| 1
.
Figure 1. Figure 2.
Front view of the Lateral view
prism of partitions. of the tower.
.
. _ _ _ _ _ _ _ _ _ _
| | | | | | | | |_| 1
| | | | | | |_|_ _| 2
| | | | |_|_ |_ _| 3
| | |_|_ |_ _ _| 4
| |_ _ |_ |_ _ _| 5
|_ _ |_ |_ _ _ _| 6
|_ | |_ _ _ _| 7
|_ |_ _ _ _ _| 8
| | 9
|_ _ _ _ _ _| 10
.
Figure 3.
Top view
of the tower.
.
Figure 1 is a two-dimensional diagram of the partitions of 10 in colexicographic order (cf. A026792, A211992). The area of the diagram is 10*42 = A066186(10) = 420. Note that the diagram can be interpreted also as the front view of a right prism whose volume is 1*10*42 = 420 equaling the volume and the number of cubes of the tower that appears in the figures 2 and 3.
Note that the shape and the area of the lateral view of the tower are the same as the shape and the area where the 1's are located in the diagram of partitions. In this case the mentioned area equals A000070(10-1) = 97.
The connection between these two associated objects is a representation of the correspondence divisor/part described in A338156. See also A336812.
The sum of the volumes of both objects equals A220909.
For the connection with the table of A338156 see also A340035. (End)
- Paolo Xausa, Table of n, a(n) for n = 1..11325 (rows 1..150 of triangle, flattened)
- T. J. Osler, A. Hassen and T. R. Chandrupatia, Surprising connections between partitions and divisors, The College Mathematics Journal, Vol. 38. No. 4, Sep. 2007, 278-287 (see p. 287).
- Omar E. Pol, Illustration of the prism, the tower and the 10th row of the triangle
Cf.
A000070,
A000203,
A026792,
A027293,
A135010,
A138137,
A176206,
A182703,
A220909,
A211992,
A221649,
A236104,
A237270,
A237271,
A237593,
A245092,
A245093,
A245095,
A245099,
A262626,
A336811,
A336812,
A338156,
A339278,
A340035,
A340583,
A340584,
A345023,
A346741.
-
nrows=12; Table[Table[DivisorSigma[1,k]PartitionsP[n-k],{k,n}],{n,nrows}] // Flatten (* Paolo Xausa, Jun 17 2022 *)
-
T(n,k)=sigma(k)*numbpart(n-k) \\ Charles R Greathouse IV, Feb 19 2013
A221530
Triangle read by rows: T(n,k) = A000005(k)*A000041(n-k).
Original entry on oeis.org
1, 1, 2, 2, 2, 2, 3, 4, 2, 3, 5, 6, 4, 3, 2, 7, 10, 6, 6, 2, 4, 11, 14, 10, 9, 4, 4, 2, 15, 22, 14, 15, 6, 8, 2, 4, 22, 30, 22, 21, 10, 12, 4, 4, 3, 30, 44, 30, 33, 14, 20, 6, 8, 3, 4, 42, 60, 44, 45, 22, 28, 10, 12, 6, 4, 2, 56, 84, 60, 66, 30, 44, 14, 20, 9, 8, 2, 6
Offset: 1
For n = 6:
-------------------------
k A000005 T(6,k)
1 1 * 7 = 7
2 2 * 5 = 10
3 2 * 3 = 6
4 3 * 2 = 6
5 2 * 1 = 2
6 4 * 1 = 4
. A000041
-------------------------
So row 6 is [7, 10, 6, 6, 4, 2]. Note that the sum of row 6 is 7+10+6+6+2+4 = 35 equals A006128(6).
.
Triangle begins:
1;
1, 2;
2, 2, 2;
3, 4, 2, 3;
5, 6, 4, 3, 2;
7, 10, 6, 6, 2, 4;
11, 14, 10, 9, 4, 4, 2;
15, 22, 14, 15, 6, 8, 2, 4;
22, 30, 22, 21, 10, 12, 4, 4, 3;
30, 44, 30, 33, 14, 20, 6, 8, 3, 4;
42, 60, 44, 45, 22, 28, 10, 12, 6, 4, 2;
56, 84, 60, 66, 30, 44, 14, 20, 9, 8, 2, 6;
...
-
A221530row[n_]:=DivisorSigma[0,Range[n]]PartitionsP[n-Range[n]];Array[A221530row,10] (* Paolo Xausa, Sep 04 2023 *)
-
row(n) = vector(n, i, numdiv(i)*numbpart(n-i)); \\ Michel Marcus, Jul 18 2014
A245095
Triangle read by rows: T(n,k) = A006218(k)*A002865(n-k).
Original entry on oeis.org
1, 0, 3, 1, 0, 5, 1, 3, 0, 8, 2, 3, 5, 0, 10, 2, 6, 5, 8, 0, 14, 4, 6, 10, 8, 10, 0, 16, 4, 12, 10, 16, 10, 14, 0, 20, 7, 12, 20, 16, 20, 14, 16, 0, 23, 8, 21, 20, 32, 20, 28, 16, 20, 0, 27, 12, 24, 35, 32, 40, 28, 32, 20, 23, 0, 29, 14, 36, 40, 56, 40, 56, 32, 40, 23, 27, 0, 35
Offset: 1
Triangle begins:
1;
0, 3;
1, 0, 5;
1, 3, 0, 8;
2, 3, 5, 0, 10;
2, 6, 5, 8, 0, 14;
4, 6, 10, 8, 10, 0, 16;
4, 12, 10, 16, 10, 14, 0, 20;
7, 12, 20, 16, 20, 14, 16, 0, 23;
8, 21, 20, 32, 20, 28, 16, 20, 0, 27;
12, 24, 35, 32, 40, 28, 32, 20, 23, 0, 29;
14, 36, 40, 56, 40, 56, 32, 40, 23, 27, 0, 35;
...
For n = 6:
-------------------------
k A006218 T(6,k)
-------------------------
1 1 * 2 = 2
2 3 * 2 = 6
3 5 * 1 = 5
4 8 * 1 = 8
5 10 * 0 = 0
6 14 * 1 = 14
. A002865
-------------------------
So row 6 is [2, 6, 5, 8, 0, 14] and the sum of row 6 is 2+6+5+8+0+14 = 35 equaling A006128(6) = 35.
-
A245095row[n_]:=Accumulate[DivisorSigma[0,Range[n]]]Reverse[Differences[PartitionsP[Range[-1,n-1]]]];Array[A245095row,10] (* Paolo Xausa, Sep 04 2023 *)
-
a006218(n) = sum(k=1, n, n\k);
a002865(n) = if(n, numbpart(n)-numbpart(n-1), 1);
row(n) = vector(n, i, a006218(i)*a002865(n-i)); \\ Michel Marcus, Jul 18 2014
A245093
Triangle read by rows in which row n lists the first n terms of A000203.
Original entry on oeis.org
1, 1, 3, 1, 3, 4, 1, 3, 4, 7, 1, 3, 4, 7, 6, 1, 3, 4, 7, 6, 12, 1, 3, 4, 7, 6, 12, 8, 1, 3, 4, 7, 6, 12, 8, 15, 1, 3, 4, 7, 6, 12, 8, 15, 13, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 28
Offset: 1
Triangle begins:
1;
1, 3;
1, 3, 4;
1, 3, 4, 7;
1, 3, 4, 7, 6;
1, 3, 4, 7, 6, 12;
1, 3, 4, 7, 6, 12, 8;
1, 3, 4, 7, 6, 12, 8, 15;
1, 3, 4, 7, 6, 12, 8, 15, 13;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12;
1, 3, 4, 7, 6, 12, 8, 15, 13, 18, 12, 28;
A340424
Triangle read by rows: T(n,k) = A024916(n-k+1)*A002865(k-1), 1 <= k <= n.
Original entry on oeis.org
1, 4, 0, 8, 0, 1, 15, 0, 4, 1, 21, 0, 8, 4, 2, 33, 0, 15, 8, 8, 2, 41, 0, 21, 15, 16, 8, 4, 56, 0, 33, 21, 30, 16, 16, 4, 69, 0, 41, 33, 42, 30, 32, 16, 7, 87, 0, 56, 41, 66, 42, 60, 32, 28, 8, 99, 0, 69, 56, 82, 66, 84, 60, 56, 32, 12, 127, 0, 87, 69, 112, 82, 132, 84, 105, 64, 48, 14
Offset: 1
Triangle begins:
1;
4, 0;
8, 0, 1;
15, 0, 4, 1;
21, 0, 8, 4, 2;
33, 0, 15, 8, 8, 2;
41, 0, 21, 15, 16 8, 4;
56, 0, 33, 21, 30, 16, 16, 4;
69, 0, 41, 33, 42, 30, 32, 16, 7;
87, 0, 56, 41, 66, 42, 60, 32, 28, 8;
99, 0, 69, 56, 82, 66, 84, 60, 56, 32, 12;
...
For n = 6 the calculation of every term of row 6 is as follows:
--------------------------
k A002865 T(6,k)
--------------------------
1 1 * 33 = 33
2 0 * 21 = 0
3 1 * 15 = 15
4 1 * 8 = 8
5 2 * 4 = 8
6 2 * 1 = 2
. A024916
--------------------------
The sum of row 6 is 33 + 0 + 15 + 8 + 8 + 2 = 66, equaling A066186(6) = 66.
A340583
Triangle read by rows: T(n,k) = A002865(n-k)*A000203(k), 1 <= k <= n.
Original entry on oeis.org
1, 0, 3, 1, 0, 4, 1, 3, 0, 7, 2, 3, 4, 0, 6, 2, 6, 4, 7, 0, 12, 4, 6, 8, 7, 6, 0, 8, 4, 12, 8, 14, 6, 12, 0, 15, 7, 12, 16, 14, 12, 12, 8, 0, 13, 8, 21, 16, 28, 12, 24, 8, 15, 0, 18, 12, 24, 28, 28, 24, 24, 16, 15, 13, 0, 12, 14, 36, 32, 49, 24, 48, 16, 30, 13, 18, 0, 28
Offset: 1
Triangle begins:
1;
0, 3;
1, 0, 4;
1, 3, 0, 7;
2, 3, 4, 0, 6;
2, 6, 4, 7, 0, 12;
4, 6, 8, 7, 6, 0, 8;
4, 12, 8, 14, 6, 12, 0, 15;
7, 12, 16, 14, 12, 12, 8, 0, 13;
8, 21, 16, 28, 12, 24, 8, 15, 0, 18;
12, 24, 28, 28, 24, 24, 16, 15, 13, 0, 12;
14, 36, 32, 49, 24, 48, 16, 30, 13, 18, 0, 28;
...
For n = 6 the calculation of every term of row 6 is as follows:
--------------------------
k A000203 T(6,k)
--------------------------
1 1 * 2 = 2
2 3 * 2 = 6
3 4 * 1 = 4
4 7 * 1 = 7
5 6 * 0 = 0
6 12 * 1 = 12
. A002865
--------------------------
The sum of row 6 is 2 + 6 + 4 + 7 + 0 + 12 = 31, equaling A138879(6).
-
A340583[n_, k_] := (PartitionsP[n - k] - PartitionsP[(n - k) - 1])*
DivisorSigma[1, k];
Table[A340583[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* Robert P. P. McKone, Jan 25 2021 *)
Showing 1-7 of 7 results.
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