A211978
Total number of parts in all partitions of n plus the sum of largest parts of all partitions of n.
Original entry on oeis.org
0, 2, 6, 12, 24, 40, 70, 108, 172, 256, 384, 550, 798, 1112, 1560, 2136, 2926, 3930, 5288, 6996, 9260, 12104, 15798, 20412, 26348, 33702, 43044, 54588, 69090, 86906, 109126, 136270, 169854, 210732, 260924, 321752, 396028, 485624, 594402, 725174, 883092, 1072208
Offset: 0
Illustration of initial terms as a minimalist diagram of regions of the set of partitions of n, for n = 1..6:
. _ _ _ _ _ _
. _ _ _ |
. _ _ _|_ |
. _ _ | |
. _ _ _ _ _ _ _|_ _|_ |
. _ _ _ | _ _ _ | |
. _ _ _ _ _ _ _|_ | _ _ _|_ | |
. _ _ | _ _ | | _ _ | | |
. _ _ _ _ _|_ | _ _|_ | | _ _|_ | | |
. _ _ _ _ | _ _ | | _ _ | | | _ _ | | | |
. _ _ | _ | | _ | | | _ | | | | _ | | | | |
. | | | | | | | | | | | | | | | | | | | | |
.
. 2 6 12 24 40 70
.
Also using the elements from the diagram we can draw an infinite Dyck path in which the n-th odd-indexed segment has A141285(n) up-steps and the n-th even-indexed segment has A194446(n) down-steps. Note that the n-th largest peak between two valleys at height 0 is also the partition number A000041(n) as shown below:
.
11...........................................................
. /\
. / \
. / \
7.................................. / \
. /\ / \
5.................... / \ /\/ \
. /\ / \ /\ / \
3.......... / \ / \ / \/ \
2..... /\ / \ /\/ \ / \
1.. /\ / \ /\/ \ / \ /\/ \
0 /\/ \/ \/ \/ \/ \
. 0,2, 6, 12, 24, 40, 70...
.
Cf.
A006128,
A135010,
A141285,
A186114,
A193870,
A187219,
A194446,
A194447,
A206437,
A211026,
A220517,
A225600,
A278355.
-
Q := sum(x^j/(1-x^j), j = 1 .. i): R := product(1-x^j, j = 1 .. i): g := sum(x^i*(1+i+Q)/R, i = 1 .. 100): gser := series(g, x = 0, 50): seq(coeff(gser, x, n), n = 0 .. 41); # Emeric Deutsch, Oct 07 2016
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Array[2 Sum[DivisorSigma[0, m] PartitionsP[# - m], {m, #}] &, 42, 0] (* Michael De Vlieger, Mar 20 2020 *)
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.
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List([0..50],n->4*NrPartitions(n)); # Muniru A Asiru, Jul 10 2018
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with(combinat): seq(4*numbpart(n),n=0..50); # Muniru A Asiru, Jul 10 2018
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4*PartitionsP[Range[0,50]] (* Harvey P. Dale, Dec 05 2023 *)
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a(n) = 4*numbpart(n); \\ Michel Marcus, Jul 15 2018
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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.
A278602
Sum of the perimeters of all regions of the n-th section of a modular table of partitions.
Original entry on oeis.org
0, 4, 8, 12, 24, 32, 60, 76, 128, 168, 256, 332, 496, 628, 896, 1152, 1580, 2008, 2716, 3416, 4528, 5688, 7388, 9228, 11872, 14708, 18684, 23088, 29004, 35632, 44440, 54288, 67168, 81756, 100384, 121656, 148552, 179192, 217556, 261544, 315836, 378232, 454748, 542584, 649500, 772532, 920912
Offset: 0
For n = 1..6, consider the modular table of partitions for the first six positive integers as shown below in the fourth quadrant of the square grid (see Figure 1):
|--------------|-----------------------------------------------------|
| Modular table| Sections |
| of partitions|-----------------------------------------------------|
| for n=1..6 | 1 2 3 4 5 6 |
1--------------|-----------------------------------------------------|
. _ _ _ _ _ _ _ _ _ _ _ _
. |_| | | | | | |_| _| | | | | | | | | |
. |_ _| | | | | |_ _| _ _| | | | | | | |
. |_ _ _| | | | |_ _ _| _ _ _| | | | | |
. |_ _| | | | |_ _| | | | | |
. |_ _ _ _| | | |_ _ _ _| _ _ _ _| | | |
. |_ _ _| | | |_ _ _| | | |
. |_ _ _ _ _| | |_ _ _ _ _| _ _ _ _ _| |
. |_ _| | | |_ _| | |
. |_ _ _ _| | |_ _ _ _| |
. |_ _ _| | |_ _ _| |
. |_ _ _ _ _ _| |_ _ _ _ _ _|
.
. Figure 1. Figure 2.
.
The table contains 11 regions, see Figure 1.
The regions are distributed in 6 sections. The Figure 2 shows the sections separately.
Then consider the following table which contains the diagram of every region separately:
---------------------------------------------------------------------
| | | | | | |
| Section | Region | Parts | Region | Peri- | a(n) |
| | |(A220482)| diagram | meter | |
---------------------------------------------------------------------
| | | | _ | | |
| 1 | 1 | 1 | |_| | 4 | 4 |
---------------------------------------------------------------------
| | | | _ | | |
| | | 1 | _| | | | |
| 2 | 2 | 2 | |_ _| | 8 | 8 |
---------------------------------------------------------------------
| | | | _ | | |
| | | 1 | | | | | |
| | | 1 | _ _| | | | |
| 3 | 3 | 3 | |_ _ _| | 12 | 12 |
---------------------------------------------------------------------
| | | | _ _ | | |
| | 4 | 2 | |_ _| | 6 | |
| |---------|---------|----------------------------| |
| | | | _ | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | _| | | | |
| | | 2 | _ _| | | | |
| 4 | 5 | 4 | |_ _ _ _| | 18 | 24 |
---------------------------------------------------------------------
| | | | _ _ _ | | |
| | 6 | 3 | |_ _ _| | 8 | |
| |---------|---------|--------------------|-------| |
| | | | _ | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | _| | | | |
| | | 2 | _ _ _| | | | |
| 5 | 7 | 5 | |_ _ _ _ _| | 24 | 32 |
---------------------------------------------------------------------
| | | | _ _ | | |
| | 8 | 2 | |_ _| | 6 | |
| |---------|---------|--------------------|-------| |
| | | | _ _ | | |
| | | 2 | _ _| | | | |
| | 9 | 4 | |_ _ _ _| | 12 | |
1 |---------|---------|--------------------|-------| |
| | | | _ _ _ | | |
| | 10 | 3 | |_ _ _| | 8 | |
| |---------|---------|--------------------|-------| |
| | | | _ | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | | | | | |
| | | 1 | _| | | | |
| | | 2 | | | | | |
| | | 2 | _| | | | |
| | | 3 | _ _ _| | | | |
| 6 | 11 | 6 | |_ _ _ _ _ _| | 34 | 60 |
---------------------------------------------------------------------
.
For n = 1..3, there is only one region in every section. The perimeters of the regions are 4, 8 and 12 respectively, so a(1) = 4, a(2) = 8, and a(3) = 12.
For n = 4, the 4th section contains two regions with perimeters 6 and 18 respectively. The sum of the perimeters is 6 + 18 = 24, so a(4) = 24.
For n = 5, the 5th section contains two regions with perimeters 8 and 24 respectively. The sum of the perimeters is 8 + 24 = 32, so a(5) = 32.
For n = 6, the 6th section contains four regions with perimeters 6, 12, 8 and 34 respectively. The sum of the perimeters is 6 + 12 + 8 + 34 = 60, so a(6) = 60.
A299473
a(n) = 3*p(n), where p(n) is the number of partitions of n.
Original entry on oeis.org
3, 3, 6, 9, 15, 21, 33, 45, 66, 90, 126, 168, 231, 303, 405, 528, 693, 891, 1155, 1470, 1881, 2376, 3006, 3765, 4725, 5874, 7308, 9030, 11154, 13695, 16812, 20526, 25047, 30429, 36930, 44649, 53931, 64911, 78045, 93555, 112014, 133749, 159522, 189783, 225525, 267402, 316674, 374262, 441819, 520575, 612678
Offset: 0
Construction of a minimalist version 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)
A000041(n): 1 2 3 5 7 11 (open regions)
A139582(n): 2 4 6 10 14 22 (line segments)
a(n)......: 3 6 9 15 21 33 (vertices)
-----------------------------------------------------------------------------------
r p(n)
-----------------------------------------------------------------------------------
.
1 .... 1 .... _| _| | _| | | _| | | | _| | | | | _| | | | | |
2 .... 2 ......... _ _| _ _| | _ _| | | _ _| | | | _ _| | | | |
3 .... 3 ................ _ _ _| _ _ _| | _ _ _| | | _ _ _| | | |
4 _ _| | _ _| | | _ _| | | |
5 .... 5 ......................... _ _ _ _| _ _ _ _| | _ _ _ _| | |
6 _ _ _| | _ _ _| | |
7 .... 7 .................................... _ _ _ _ _| _ _ _ _ _| |
8 _ _| | |
9 _ _ _ _| |
10 _ _ _| |
11 .. 11 ................................................. _ _ _ _ _ _|
.
The r-th horizontal line segment has length A141285(r).
The r-th vertical line segment has length A194446(r).
An infinite diagram is a minimalist table of all partitions of all positive integers.
Cf.
A135010,
A141285,
A182181,
A186114,
A193870,
A194446,
A194447,
A206437,
A207779,
A220482,
A220517,
A273140,
A278355,
A278602,
A299475.
A338969
a(n) is the sum of the lengths of all the segments used to draw a rectangle of height partition(n) and width n divided into partition(n) rectangles of unit height, in turn, divided into rectangles of unit height and lengths corresponding to the parts of the partitions of n.
Original entry on oeis.org
4, 11, 21, 41, 67, 118, 181, 292, 437, 664, 958, 1412, 1983, 2819, 3899, 5406, 7328, 9977, 13317, 17817, 23497, 30967, 40349, 52573, 67784, 87320, 111601, 142395, 180432, 228317, 287110, 360476, 450261, 561346, 696699, 863199, 1065055, 1311824, 1610026, 1972444
Offset: 1
Illustrations for n = 1..6:
_ _ _ _ _ _
|_| |_ _| |_ _ _|
|_|_| |_ _|_|
|_|_|_|
a(1) = 4 a(2) = 11 a(3) = 21
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _
|_ _ _ _| |_ _ _ _ _| |_ _ _ _ _ _|
|_ _ _|_| |_ _ _ _|_| |_ _ _ _ _|_|
|_ _|_ _| |_ _ _|_ _| |_ _ _ _|_ _|
|_ _|_|_| |_ _ _|_|_| |_ _ _ _|_|_|
|_|_|_|_| |_ _|_ _|_| |_ _ _|_ _ _|
|_ _|_|_|_| |_ _ _|_ _|_|
|_|_|_|_|_| |_ _ _|_|_|_|
|_ _|_ _|_ _|
|_ _|_ _|_|_|
|_ _|_|_|_|_|
|_|_|_|_|_|_|
a(4) = 41 a(5) = 67 a(6) = 118
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a[n_]:=(n+1)PartitionsP[n]+n+Sum[DivisorSigma[0,m] PartitionsP[n-m], {m,n}]; Table[a[n],{n,40}]
Showing 1-6 of 6 results.
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