A210990
Total area of the shadows of the three views of the shell model of partitions with n regions.
Original entry on oeis.org
0, 3, 10, 21, 26, 44, 51, 75, 80, 92, 99, 136, 143, 157, 166, 213, 218, 230, 237, 260, 271, 280, 348, 355, 369, 378, 403, 410, 427, 438, 526, 531, 543, 550, 573, 584, 593, 631, 640, 659, 672, 683, 804, 811, 825, 834, 859, 866, 883, 894, 938, 949, 958
Offset: 0
For n = 11 the three views of the shell model of partitions with 11 regions look like this:
.
. A182181(11) = 35 A182244(11) = 66
.
. 6 * * * * * 6
. 3 3 P * * 3 * * 3
. 2 4 a * * * 4 * 2
. 2 2 2 r * 2 * 2 * 2
. 1 5 t * * * * 5 1
. 1 2 3 i * * 3 * 2 1
. 1 1 4 t * * * 4 1 1
. 1 1 2 2 i * 2 * 2 1 1
. 1 1 1 3 o * * 3 1 1 1
. 1 1 1 1 2 n * 2 1 1 1 1
. 1 1 1 1 1 1 s 1 1 1 1 1 1
. <------- Regions ------ ------------> N
. L
. a 1
. r * 2
. g * * 3
. e * 2
. s * * * 4
. t * * 3
. * * * * 5
. p * 2
. a * * * 4
. r * * 3
. t * * * * * 6
. s
. A182727(11) = 35
.
The areas of the shadows of the three views are A182244(11) = 66, A182181(11) = 35 and A182727(11) = 35, therefore the total area of the three shadows is 66+35+35 = 136, so a(11) = 136.
A193827
Irregular triangle read by rows in which row n lists the emergent parts of all partitions of n, or 0 if such parts do not exist.
Original entry on oeis.org
0, 0, 0, 0, 2, 3, 2, 2, 4, 3, 3, 2, 5, 4, 2, 2, 4, 3, 2, 2, 3, 6, 5, 4, 3, 2, 5, 4, 2, 2, 3, 7, 3, 3, 6, 5, 2, 2, 4, 3, 2, 2, 3, 6, 5, 4, 2, 2, 2, 2, 3, 4, 8, 4, 3, 7, 6, 5, 3, 2, 5, 4, 2, 2, 3, 7, 3, 3, 6, 5, 2, 2, 2, 2, 3, 3, 4, 9, 5, 4, 3, 4, 8, 7, 6
Offset: 0
If written as a triangle:
0,
0,
0,
0,
2,
3,
2,2,4,3,
3,2,5,4,
2,2,4,3,2,2,3,6,5,4,
3,2,5,4,2,2,3,7,3,3,6,5,
2,2,4,3,2,2,3,6,5,4,2,2,2,2,3,4,8,4,3,7,6,5,
3,2,5,4,2,2,3,7,3,3,6,5,2,2,2,2,3,3,4,9,5,4,3,4,8,7,6
A220482
Triangle read by rows: T(j,k) in which row j lists the parts in nondecreasing order of the j-th region of the set of partitions of n, with 1<=j<=A000041(n).
Original entry on oeis.org
1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 4, 3, 1, 1, 1, 1, 1, 2, 5, 2, 2, 4, 3, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 6, 3, 2, 5, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 7, 2, 2, 4, 3, 2, 2, 3, 6, 5, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 4, 8
Offset: 1
First 15 rows of the irregular triangle are
1;
1, 2;
1, 1, 3;
2;
1, 1, 1, 2, 4;
3;
1, 1, 1, 1, 1, 2, 5;
2;
2, 4;
3;
1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 6;
3;
2, 5;
4;
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 7;
A194448
Number of parts > 1 in the n-th region of the shell model of partitions.
Original entry on oeis.org
0, 1, 1, 1, 2, 1, 2, 1, 2, 1, 4, 1, 2, 1, 4, 1, 2, 1, 4, 1, 1, 7, 1, 2, 1, 4, 1, 2, 1, 8, 1, 2, 1, 4, 1, 1, 7, 1, 2, 1, 1, 12, 1, 2, 1, 4, 1, 2, 1, 8, 1, 1, 3, 1, 1, 14, 1, 2, 1, 4, 1, 1, 7, 1, 2, 1, 1, 12, 1, 2, 1, 4, 1, 2, 1, 1, 21, 1, 2, 1, 4, 1, 2
Offset: 1
Written as a triangle:
0;
1;
1;
1,2;
1,2;
1,2,1,4;
1,2,1,4;
1,2,1,4,1,1,7;
1,2,1,4,1,2,1,8;
1,2,1,4,1,1,7,1,2,1,1,12;
1,2,1,4,1,2,1,8,1,1,3,1,1,14;
1,2,1,4,1,1,7,1,2,1,1,12,1,2,1,4,1,2,1,1,21;
Cf.
A000041,
A002865,
A135010,
A138121,
A138137,
A138879,
A186114,
A186412,
A193870,
A194436,
A194437,
A194438,
A194439,
A194446,
A194447,
A194449.
A210991
Total area of the shadows of the three views of the shell model of partitions with n regions.
Original entry on oeis.org
0, 3, 9, 18, 21, 35, 39, 58, 61, 67, 71, 99, 103, 110, 115, 152, 155, 161, 165, 175, 181, 186, 238, 242, 249, 254, 265, 269, 277, 283, 352, 355, 361, 365, 375, 381, 386, 401, 406, 415, 422, 428, 522, 526, 533, 538, 549, 553, 561, 567, 584, 590, 595, 606
Offset: 0
For n = 11 the three views of the shell model of partitions with 11 regions look like this:
.
. A182181(11) = 35 A210692(11) = 29
.
. 1 1
. 1 1
. 1 1
. 1 1
. 1 1 1 1
. 1 1 1 1
. 1 1 1 1 1 1
. 2 1 1 1 1 2
. 2 1 1 1 1 1 1 2
. 3 2 2 2 1 1 1 1 2 2 3
. 6 3 4 2 5 3 4 2 3 2 1 1 2 3 4 5 6
. <------- Regions ------ ------------> N
. L
. a 1
. r * 2
. g * * 3
. e * 2
. s * * * 4
. t * * 3
. * * * * 5
. p * 2
. a * * * 4
. r * * 3
. t * * * * * 6
. s
.
. A182727(11) = 35
.
The areas of the shadows of the three views are A182181(11) = 35, A182727(11) = 35 and A210692(11) = 29, therefore the total area of the three shadows is 35+35+29 = 99, so a(11) = 99.
Since n = 11 is a partition number A000041 we can see that the rotated structure with 11 regions shows each row as a partition of 6 because A000041(6) = 11. See below:
.
. 6
. 3 3
. 4 2
. 2 2 2
. 5 1
. 3 2 1
. 4 1 1
. 2 2 1 1
. 3 1 1 1
. 2 1 1 1 1
. 1 1 1 1 1 1
.
Cf.
A000041,
A026905,
A135010,
A138121,
A141285,
A182703,
A194446,
A182181,
A182727,
A186114,
A206437,
A210692.
A299474
a(n) = 4*p(n), where p(n) is the number of partitions of n.
Original entry on oeis.org
4, 4, 8, 12, 20, 28, 44, 60, 88, 120, 168, 224, 308, 404, 540, 704, 924, 1188, 1540, 1960, 2508, 3168, 4008, 5020, 6300, 7832, 9744, 12040, 14872, 18260, 22416, 27368, 33396, 40572, 49240, 59532, 71908, 86548, 104060, 124740, 149352, 178332, 212696, 253044, 300700, 356536, 422232, 499016, 589092, 694100, 816904
Offset: 0
Construction of a modular table of partitions in which a(n) is the number of edges of the diagram after n-th stage (n = 1..6):
--------------------------------------------------------------------------------
n ........: 1 2 3 4 5 6 (stage)
a(n)......: 4 8 12 20 28 44 (edges)
A299475(n): 4 7 10 16 22 34 (vertices)
A000041(n): 1 2 3 5 7 11 (regions)
--------------------------------------------------------------------------------
r p(n)
--------------------------------------------------------------------------------
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 .... 1 ....|_| |_| | |_| | | |_| | | | |_| | | | | |_| | | | | |
2 .... 2 .........|_ _| |_ _| | |_ _| | | |_ _| | | | |_ _| | | | |
3 .... 3 ................|_ _ _| |_ _ _| | |_ _ _| | | |_ _ _| | | |
4 |_ _| | |_ _| | | |_ _| | | |
5 .... 5 .........................|_ _ _ _| |_ _ _ _| | |_ _ _ _| | |
6 |_ _ _| | |_ _ _| | |
7 .... 7 ....................................|_ _ _ _ _| |_ _ _ _ _| |
8 |_ _| | |
9 |_ _ _ _| |
10 |_ _ _| |
11 .. 11 .................................................|_ _ _ _ _ _|
.
Apart from the axis x, the r-th horizontal line segment has length A141285(r), equaling the largest part of the r-th region of the diagram.
Apart from the axis y, the r-th vertical line segment has length A194446(r), equaling the number of parts in the r-th region of the diagram.
The total number of parts equals the sum of largest parts.
Note that every diagram contains all previous diagrams.
An infinite diagram is a table of all partitions of all positive integers.
Cf.
A135010,
A141285,
A182181,
A186114,
A193870,
A194446,
A194447,
A206437,
A207779,
A220482,
A220517,
A273140,
A278355,
A278602,
A299475.
-
List([0..50],n->4*NrPartitions(n)); # Muniru A Asiru, Jul 10 2018
-
with(combinat): seq(4*numbpart(n),n=0..50); # Muniru A Asiru, Jul 10 2018
-
4*PartitionsP[Range[0,50]] (* Harvey P. Dale, Dec 05 2023 *)
-
a(n) = 4*numbpart(n); \\ Michel Marcus, Jul 15 2018
-
from sympy.ntheory import npartitions
def a(n): return 4*npartitions(n)
print([a(n) for n in range(51)]) # Michael S. Branicky, Apr 04 2021
A299475
a(n) is the number of vertices in the diagram of partitions of n (see example).
Original entry on oeis.org
1, 4, 7, 10, 16, 22, 34, 46, 67, 91, 127, 169, 232, 304, 406, 529, 694, 892, 1156, 1471, 1882, 2377, 3007, 3766, 4726, 5875, 7309, 9031, 11155, 13696, 16813, 20527, 25048, 30430, 36931, 44650, 53932, 64912, 78046, 93556, 112015, 133750, 159523, 189784, 225526, 267403, 316675, 374263, 441820, 520576, 612679
Offset: 0
Construction of a modular table of partitions in which a(n) is the number of vertices of the diagram after n-th stage (n = 1..6):
--------------------------------------------------------------------------------
n ........: 1 2 3 4 5 6 (stage)
a(n)......: 4 7 10 16 22 34 (vertices)
A299474(n): 4 8 12 20 28 44 (edges)
A000041(n): 1 2 3 5 7 11 (regions)
--------------------------------------------------------------------------------
r p(n)
--------------------------------------------------------------------------------
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 .... 1 ....|_| |_| | |_| | | |_| | | | |_| | | | | |_| | | | | |
2 .... 2 .........|_ _| |_ _| | |_ _| | | |_ _| | | | |_ _| | | | |
3 .... 3 ................|_ _ _| |_ _ _| | |_ _ _| | | |_ _ _| | | |
4 |_ _| | |_ _| | | |_ _| | | |
5 .... 5 .........................|_ _ _ _| |_ _ _ _| | |_ _ _ _| | |
6 |_ _ _| | |_ _ _| | |
7 .... 7 ....................................|_ _ _ _ _| |_ _ _ _ _| |
8 |_ _| | |
9 |_ _ _ _| |
10 |_ _ _| |
11 .. 11 .................................................|_ _ _ _ _ _|
.
Apart from the axis x, the r-th horizontal line segment has length A141285(r), equaling the largest part of the r-th region of the diagram.
Apart from the axis y, the r-th vertical line segment has length A194446(r), equaling the number of parts in the r-th region of the diagram.
The total number of parts equals the sum of largest parts.
Note that every diagram contains all previous diagrams.
An infinite diagram is a table of all partitions of all positive integers.
Cf.
A000041,
A135010,
A139582,
A141285,
A182181,
A186114,
A193870,
A194446,
A194447,
A206437,
A207779,
A220482,
A220517,
A273140,
A278355,
A278602,
A299474.
A182727
Sum of largest parts of the shell model of partitions with n regions.
Original entry on oeis.org
1, 3, 6, 8, 12, 15, 20, 22, 26, 29, 35, 38, 43, 47, 54, 56, 60, 63, 69, 74, 78, 86, 89, 94, 98, 105, 108, 114, 119, 128, 130, 134, 137, 143, 148, 152, 160, 164, 171, 177, 182, 192, 195, 200, 204, 211, 214, 220, 225, 234, 239, 243, 251, 258, 264, 275, 277, 281
Offset: 1
For n = 6 the largest parts of the first six regions of the shell model of partitions are 1, 2, 3, 2, 4, 3, so a(6) = 1+2+3+2+4+3 = 15.
Written as a triangle begins:
1;
3;
6;
8, 12;
15, 20;
22, 26, 29, 35;
38, 43, 47, 54;
56, 60, 63, 69, 74, 78, 86;
89, 94, 98,105,108,114,119,128;
130,134,137,143,148,152,160,164,171,177,182,192;
195,200,204,211,214,220,225,234,239,243,251,258,264,275;
A228349
Triangle read by rows: T(j,k) is the k-th part in nondecreasing order of the j-th region of the set of compositions (ordered partitions) of n in colexicographic order, if 1<=j<=2^(n-1) and 1<=k<=A006519(j).
Original entry on oeis.org
1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 3, 4, 1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 5, 1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 3, 4, 1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1
Offset: 1
----------------------------------------------------------
. Diagram Triangle
Compositions of of compositions (rows)
of 5 regions and regions (columns)
----------------------------------------------------------
. _ _ _ _ _
5 |_ | 5
1+4 |_|_ | 1 4
2+3 |_ | | 2 3
1+1+3 |_|_|_ | 1 1 3
3+2 |_ | | 3 2
1+2+2 |_|_ | | 1 2 2
2+1+2 |_ | | | 2 1 2
1+1+1+2 |_|_|_|_ | 1 1 1 2
4+1 |_ | | 4 1
1+3+1 |_|_ | | 1 3 1
2+2+1 |_ | | | 2 2 1
1+1+2+1 |_|_|_ | | 1 1 2 1
3+1+1 |_ | | | 3 1 1
1+2+1+1 |_|_ | | | 1 2 1 1
2+1+1+1 |_ | | | | 2 1 1 1
1+1+1+1+1 |_|_|_|_|_| 1 1 1 1 1
.
Written as an irregular triangle in which row n lists the parts of the n-th region the sequence begins:
1;
1,2;
1;
1,1,2,3;
1;
1,2;
1;
1,1,1,1,2,2,3,4;
1;
1,2;
1;
1,1,2,3;
1;
1,2;
1;
1,1,1,1,1,1,1,1,2,2,2,2,3,3,4,5;
...
Alternative interpretation of this sequence:
Triangle read by rows in which row r lists the regions of the last section of the set of compositions of r:
[1];
[1,2];
[1],[1,1,2,3];
[1],[1,2],[1],[1,1,1,1,2,2,3,4];
[1],[1,2],[1],[1,1,2,3],[1],[1,2],[1],[1,1,1,1,1,1,1,1,2,2,2,2,3,3,4,5];
Cf.
A001787,
A001792,
A011782,
A029837,
A045623,
A065120,
A070939,
A090996,
A186114,
A187816,
A187818,
A206437,
A220482,
A228347,
A228348,
A228350,
A228351,
A228366,
A228367,
A228370,
A228371,
A228525,
A228526.
-
Table[Map[Length@ TakeWhile[IntegerDigits[#, 2], # == 1 &] &, Range[2^(# - 1), 2^# - 1]] &@ IntegerExponent[2 n, 2], {n, 32}] // Flatten (* Michael De Vlieger, May 23 2017 *)
A210942
Triangle read by rows in which row n lists the parts > 1 of the n-th region of the shell model of partitions, with a(1) = 1.
Original entry on oeis.org
1, 2, 3, 2, 4, 2, 3, 5, 2, 2, 4, 2, 3, 6, 3, 2, 2, 3, 5, 2, 4, 7, 3, 2, 2, 2, 4, 2, 3, 6, 3, 2, 2, 5, 4, 8, 4, 3, 2, 2, 2, 2, 3, 5, 2, 4, 7, 3, 2, 2, 3, 6, 3, 5, 9, 4, 3, 3, 2, 2, 2, 2, 2, 4, 2, 3, 6, 3, 2, 2, 5, 4, 8, 4, 3, 2, 2, 2, 2, 4, 7, 3, 6, 5, 10, 5
Offset: 1
Written as a triangle begins:
1;
2;
3;
2;
4,2;
3;
5,2,
2;
4,2;
3;
6,3,2,2;
3;
5,2;
4;
7,3,2,2;
Cf.
A135010,
A138121,
A182699,
A182709,
A183152,
A186114,
A187219,
A194436-
A194439,
A194447-
A194448,
A196025,
A198381,
A206437,
A210941.
Comments