cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A338964 Number of oriented colorings of the 120 dodecahedral facets of the 4-D 120-cell (or 120 vertices of the 4-D 600-cell) using subsets of a set of n colors.

Original entry on oeis.org

1, 184614999414571937405905419562272, 249584763877004334779608333505026056531601345365910986, 245395425663664490219902430658740012166428009430164733569180712873472
Offset: 1

Views

Author

Robert A. Russell, Dec 04 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. The Schläfli symbols of the 120-cell and 600-cell are {5,3,3} and {3,3,5} respectively. They are mutually dual. There are 7200 elements in the rotation group of the 120-cell. They divide into 41 conjugacy classes. The first formula is obtained by averaging the vertex (or facet) cycle indices after replacing x_i^j with n^j according to the Pólya enumeration theorem.
Count Even Cycle Indices Count Even Cycle Indices
1 x_1^120 400 x_2^3x_6^19
450 x_1^4x_2^58 20+20 x_6^20
1 x_2^60 144+144 x_2^5x_10^11
400 x_1^6x_3^38 4*12+2*144 x_10^12
20+20 x_3^40 600+600 x_12^10
144+144 x_1^10x_5^22 4*240 x_15^8
30+30 x_4^30 4*360 x_20^6
4*12+2*144 x_5^24 4*240 x_30^4
Sequences for other elements of the 120-cell and 600-cell are not suitable for the OEIS as the first significant datum is too big. We provide formulas here.
For the 600 facets of the 600-cell (vertices of the 120-cell), the cycle indices are:
Count Even Cycle Indices Count Even Cycle Indices
1 x_1^600 400 x_2^6x_6^98
450 x_1^4x_2^298 20+20 x_6^100
1 x_2^300 4*12+4*144 x_10^60
400 x_1^12x_3^196 600+600 x_12^50
20+20 x_3^200 4*240 x_15^40
30+30 x_4^150 4*360 x_20^30
4*12+4*144 x_5^120 4*240 x_30^20
The formula is (960*n^20 + 1440*n^30 + 960*n^40 + 1200*n^50 + 624*n^60 + 40*n^100 + 400*n^104 + 624*n^120 + 60*n^150 + 40*n^200 + 400*n^208 + n^300 + 450*n^302 + n^600) / 7200.
For the 720 pentagonal faces of the 120-cell (edges of the 600-cell), the cycle indices are:
Count Even Cycle Indices Count Even Cycle Indices
1 x_1^720 2*20+400 x_6^120
450 x_1^8x_2^356 144+144 x_2^5x_10^71
1 x_2^360 4*12+2*144 x_10^72
2*20+400 x_3^240 600+600 x_12^60
30+30 x_4^180 4*240 x_15^48
144+144 x_1^10x_5^142 4*360 x_20^36
4*12+2*144 x_5^144 4*240 x_30^24
The formula is (960*n^24 + 1440*n^36 + 960*n^48 + 1200*n^60 + 336*n^72 + 288*n^76 + 440*n^120 + 336*n^144 + 288*n^152 + 60*n^180 + 440*n^240 + n^360 + 450*n^364 + n^720) / 7200.
For the 1200 edges of the 120-cell (triangular faces of the 600-cell), the cycle indices are:
Count Even Cycle Indices Count Even Cycle Indices
1 x_1^1200 400 x_2^3x_6^199
450 x_1^8x_2^596 20+20 x_6^200
1 x_2^600 4*12+4*144 x_10^120
400 x_1^6x_3^398 600+600 x_12^100
20+20 x_3^400 4*240 x_15^80
30+30 x_4^300 4*360 x_20^60
4*12+4*144 x_5^240 4*240 x_30^40
The formula is (960*n^40 + 1440*n^60 + 960*n^80 + 1200*n^100 + 624*n^120 + 40*n^200 + 400*n^202 + 624*n^240 + 60*n^300 + 40*n^400 + 400*n^404 + n^600 + 450*n^604 + n^1200) / 7200.

Crossrefs

Cf. A338965 (unoriented), A338966 (chiral), A338967 (achiral), A338980 (exactly n colors), A337895 (5-cell), A337952 (8-cell vertices, 16-cell facets), A337956(16-cell vertices, 8-cell facets), A338948 (24-cell).

Programs

  • Mathematica
    Table[(960n^4+1440n^6+960n^8+1200n^10+336n^12+288n^16+40n^20+400n^22+336n^24+60n^30+288n^32+40n^40+400n^44 +n^60+450n^62 +n^120)/7200,{n,10}]
  • PARI
    a(n)=(960*n^4+1440*n^6+960*n^8+1200*n^10+336*n^12+288*n^16+40*n^20+400*n^22+336*n^24+60*n^30+288*n^32+40*n^40+400*n^44+n^60+450*n^62+n^120)/7200 \\ Charles R Greathouse IV, Jul 05 2024

Formula

a(n) = (960*n^4 + 1440*n^6 + 960*n^8 + 1200*n^10 + 336*n^12 + 288*n^16 + 40*n^20 + 400*n^22 + 336*n^24 + 60* n^30 + 288*n^32 + 40*n^40 + 400*n^44 + n^60 + 450*n^62 + n^120) / 7200.
a(n) = Sum_{j=1..Min(n,120)} A338980(n) * binomial(n,j).
a(n) = A338965(n) + A338966(n) = 2*A338965(n) - A338967(n) = 2*A338966(n) + A338967(n).

A338948 Number of oriented colorings of the 24 octahedral facets (or 24 vertices) of the 4-D 24-cell using subsets of a set of n colors.

Original entry on oeis.org

1, 30968, 490710246, 488689596200, 103480643539150, 8226360697111116, 332606338581801018, 8198553131754111456, 138483409168412322525, 1736111115543474313600, 17100230356306262961356, 138015359782116886130568
Offset: 1

Views

Author

Robert A. Russell, Nov 17 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. The Schläfli symbol of the 24-cell is {3,4,3}. It is self-dual. There are 576 elements in the rotation group of the 24-cell. They divide into 20 conjugacy classes. The first formula is obtained by averaging the vertex (or facet) cycle indices after replacing x_i^j with n^j according to the Pólya enumeration theorem.
Count Even Cycle Indices Count Even Cycle Indices
1 x_1^24 36 x_2^2x_4^5
18 x_1^4x_2^10 32 x_2^3x_6^3
72 x_1^2x_2^11 6+6 x_4^6
1 x_2^12 8+8+32 x_6^4
32 x_1^6x_3^6 72+72 x_8^3
36 x_1^4x_4^5 48+48 x_12^2
8+8+32 x_3^8

Crossrefs

Cf. A338949 (unoriented), A338950 (chiral), A338951 (achiral), A338952 (edges, faces), A337895 (5-cell), A337952 (8-cell vertices, 16-cell facets), A337956 (16-cell vertices, 8-cell facets), A338964 (120-cell, 600-cell).

Programs

  • Mathematica
    Table[(96n^2+144n^3+48n^4+44n^6+36n^7+48n^8+36n^9+33n^12+72n^13+18n^14+n^24)/576,{n,15}]

Formula

a(n) = (96*n^2 + 144*n^3 + 48*n^4 + 44*n^6 + 36*n^7 + 48*n^8 + 36*n^9 + 33*n^12 + 72*n^13 + 18*n^14 + n^24) / 576.
a(n) = 1*C(n,1) + 30966*C(n,2) + 490617345*C(n,3) + 486726941020*C(n,4) + 101042102350935*C(n,5) + 7612797366078810*C(n,6) + 277177820254686645*C(n,7) + 5762279787373449480*C(n,8) + 75992221900428179850*C(n,9) + 682000715348622816300*C(n,10) + 4372841482811937689400*C(n,11) + 20731958137729666674000*C(n,12) + 74473828855001644068000*C(n,13) + 206154110634594043521600*C(n,14) + 444564429725793817440000*C(n,15) + 751083930907369899840000*C(n,16) + 994782360855398955840000*C(n,17) + 1027991414661948696960000*C(n,18) + 819571017352669021440000*C(n,19) + 494068244672052610560000*C(n,20) + 217722453472796912640000*C(n,21) + 66156028946382735360000*C(n,22) + 12387424687382384640000*C(n,23) + 1077167364120207360000*C(n,24), where the coefficient of C(n,k) is the number of oriented colorings using exactly k colors.
a(n) = A338949(n) + A338950(n) = 2*A338949(n) - A338951(n) = 2*A338950(n) + A338951(n).

A128767 Number of inequivalent n-colorings of the 4D hypercube under the full orthogonal group of the cube (of order 2^4*4! = 384).

Original entry on oeis.org

1, 402, 132102, 11756666, 405385550, 7416923886, 86986719477, 735192450952, 4834517667381, 26073250910950, 119759687845446, 481750080584202, 1733588303252702, 5673534527793146, 17109303241791825, 48047227408513056
Offset: 1

Views

Author

Ricardo Perez-Aguila (ricardo.perez.aguila(AT)gmail.com), Apr 04 2007

Keywords

Comments

I assume this refers to colorings of the vertices of the cube. - N. J. A. Sloane, Apr 06 2007
Number of unoriented colorings of the 16 tetrahedral facets of a hyperoctahedron or of the 16 vertices of a tesseract (4-D cube) using up to n colors. Each chiral pair is counted as one when enumerating unoriented arrangements. The Schläfli symbols for the tesseract and the hyperoctahedron are {4,3,3} and {3,3,4} respectively. Both figures are regular 4-D polyhedra and they are mutually dual. - Robert A. Russell, Oct 03 2020

Examples

			a(2)=402 because there are 402 inequivalent 2-colorings of the 4D hypercube.
		

References

  • Banks, D. C.; Linton, S. A. & Stockmeyer, P. K. Counting Cases in Substitope Algorithms. IEEE Transactions on Visualization and Computer Graphics, Vol. 10, No. 4, pp. 371-384. 2004.
  • Perez-Aguila, Ricardo. Enumerating the Configurations in the n-Dimensional Orthogonal Polytopes Through Polya's Counting and A Concise Representation. Proceedings of the 3rd International Conference on Electrical and Electronics Engineering and XII Conference on Electrical Engineering ICEEE and CIE 2006, pp. 63-66.
  • Polya, G. & Read R. C. Combinatorial Enumeration of Groups, Graphs and Chemical Compounds. Springer-Verlag, 1987.

Crossrefs

Cf. A337952 (oriented), A337954 (chiral), A337955 (achiral).
Other elements: A331359 (tesseract edges, hyperoctahedron faces), A331355 (tesseract faces, hyperoctahedron edges), A337957 (tesseract facets, hyperoctahedron vertices).
Other polychora: A000389(n+4) (4-simplex facets/vertices), A338949 (24-cell), A338965 (120-cell, 600-cell).
Row 4 of A325013 (orthoplex facets, orthotope vertices).

Programs

  • Mathematica
    Table[(1/384)*( 48*n^2 + 180*n^4 + 48*n^6 + 83*n^8 + 12*n^10 + 12*n^12 + n^16),{n,30}]

Formula

a(n) = (1/384)*(48*n^2 + 180*n^4 + 48*n^6 + 83*n^8 + 12*n^10 + 12*n^12 + n^16)
G.f.: -x*(x +1)*(x^14 +384*x^13 +125020*x^12 +9439904*x^11 +213777216*x^10 +1821620108*x^9 +6527222787*x^8 +10098845160*x^7 +6527222787*x^6 +1821620108*x^5 +213777216*x^4 +9439904*x^3 +125020*x^2 +384*x +1) / (x -1)^17. [Colin Barker, Dec 04 2012]
From Robert A. Russell, Oct 03 2020: (Start)
a(n) = 1*C(n,1) + 400*C(n,2) + 130899*C(n,3) + 11230666*C(n,4) + 347919225*C(n,5) + 5158324560*C(n,6) + 43174480650*C(n,7) + 225086553300*C(n,8) + 775894225050*C(n,9) + 1831178115900*C(n,10) + 3008073915000*C(n,11) + 3439243962000*C(n,12) + 2685727044000*C(n,13) + 1366701336000*C(n,14) + 408648240000*C(n,15) + 54486432000*C(n,16), where the coefficient of C(n,k) is the number of unoriented colorings using exactly k colors.
a(n) = A337952(n) - A337954(n) = (A337952(n) + A337955(n)) / 2 = A337954(n) + A337955(n).
(End)

A337895 Number of oriented colorings of the tetrahedral facets (or vertices) of a regular 4-dimensional simplex using n or fewer colors.

Original entry on oeis.org

1, 6, 21, 56, 127, 258, 483, 848, 1413, 2254, 3465, 5160, 7475, 10570, 14631, 19872, 26537, 34902, 45277, 58008, 73479, 92114, 114379, 140784, 171885, 208286, 250641, 299656, 356091, 420762, 494543, 578368, 673233
Offset: 1

Views

Author

Robert A. Russell, Sep 28 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. Also called a 5-cell or pentachoron. The Schläfli symbol is {3,3,3}, and it has 5 tetrahedral facets (vertices).
There are 60 elements in the rotation group of the 4-dimensional simplex. Each is an even permutation of the vertices and can be associated with a partition of 5 based on the conjugacy class of the permutation. The first formula is obtained by averaging their cycle indices after replacing x_i^j with n^j according to the Pólya enumeration theorem.
Partition Count Even Cycle Indices
5 24 x_5^1
311 20 x_1^2x_3^1
221 15 x_1^1x_2^2
11111 1 x_1^5

Examples

			For a(2)=6, the colors are AAAAA, AAAAB, AAABB, AABBB, ABBBB, and BBBBB.
		

Crossrefs

Cf. A000389(n+4) (unoriented), A000389(chiral), A132366(n-1) (achiral), A331350 (edges, faces), A337952 (8-cell vertices, 16-cell facets), A337956(16-cell vertices, 8-cell facets), A338948 (24-cell), A338964 (120-cell, 600-cell).
Row 4 of A324999 (oriented colorings of facets or vertices of an n-simplex).

Programs

  • Mathematica
    Table[n (24 + 35 n^2 + n^4)/60, {n, 40}]

Formula

a(n) = n * (24 + 35*n^2 + n^4) / 60.
a(n) = binomial[4+n,5] + binomial[n,5].
a(n) = 1*C(n,1) + 4*C(n,2) + 6*C(n,3) + 4*C(n,4) + 2*C(n,5), where the coefficient of C(n,k) is the number of oriented colorings using exactly k colors.
a(n) = A000389(n+4) + A000389(n) = 2*A000389(n+4) - A132366(n-1) = 2*A000389(n) + A132366(n-1).

A337954 Number of chiral pairs of colorings of the 16 tetrahedral facets of a hyperoctahedron or of the 16 vertices of a tesseract.

Original entry on oeis.org

0, 94, 97974, 10700090, 390081800, 7280687610, 86121007714, 730895668104, 4816861200630, 26010740238450, 119563513291420, 481192778757834, 1732132086737234, 5669991002636870, 17101193825828700, 48029634770843680
Offset: 1

Views

Author

Robert A. Russell, Oct 03 2020

Keywords

Comments

Each member of a chiral pair is a reflection, but not a rotation, of the other. The Schläfli symbols for the tesseract and the hyperoctahedron are {4,3,3} and {3,3,4} respectively. Both figures are regular 4-D polyhedra and they are mutually dual.

Crossrefs

Cf. A337952 (oriented), A128767 (unoriented), A337955 (achiral).
Other elements: A331360 (tesseract edges, hyperoctahedron faces), A331356 (tesseract faces, hyperoctahedron edges), A234249(n+1) (tesseract facets, hyperoctahedron vertices).
Other polychora: A000389 (4-simplex facets/vertices), A338950 (24-cell), A338966 (120-cell, 600-cell).
Row 4 of A325014 (orthoplex facets, orthotope vertices).

Programs

  • Mathematica
    Table[(n^16-12n^12+12n^10+43n^8-48n^6-44n^4+48n^2)/384,{n, 30}]

Formula

a(n) = (n-1) * n^2 * (n+1) * (n^12 + n^10 - 11*n^8 + n^6 + 44 n^4 - 4 n^2 - 48) / 384.
a(n) = 94*C(n,2) + 97692*C(n,3) + 10308758*C(n,4) + 337560150*C(n,5) + 5098740090*C(n,6) + 42976836210*C(n,7) + 224685801060*C(n,8) + 775389028050*C(n,9) + 1830791421900*C(n,10) + 3007909258200*C(n,11) + 3439214024400*C(n,12) + 2685727044000*C(n,13) + 1366701336000*C(n,14) + 408648240000*C(n,15) + 54486432000*C(n,16), where the coefficient of C(n,k) is the number of chiral pairs of colorings using exactly k colors.
a(n) = A337952(n) - A128767(n) = (A337952(n) - A337955(n)) / 2 = A128767(n) - A337955(n).

A337955 Number of achiral colorings of the 16 tetrahedral facets of a hyperoctahedron or of the 16 vertices of a tesseract.

Original entry on oeis.org

1, 308, 34128, 1056576, 15303750, 136236276, 865711763, 4296782848, 17656466751, 62510672500, 196174554026, 557301826368, 1456216515468, 3543525156276, 8109415963125, 17592637669376, 36414622551373
Offset: 1

Views

Author

Robert A. Russell, Oct 03 2020

Keywords

Comments

An achiral coloring is identical to its reflection. The Schläfli symbols for the tesseract and the hyperoctahedron are {4,3,3} and {3,3,4} respectively. Both figures are regular 4-D polyhedra and they are mutually dual. There are 192 elements in the automorphism group of the tesseract that are not in its rotation group. Each involves a permutation of the axes that can be associated with a partition of 4 based on the conjugacy class of the permutation. This table shows the hyperoctahedron facet (tesseract vertex) cycle indices for each member of such a class. The first formula is obtained by averaging these cycle indices after replacing x_i^j with n^j according to the Pólya enumeration theorem.
Partition Count Odd Cycle Indices
4 6 8x_1^2x_2^1x_4^3
31 8 8x_2^2x_6^2
22 3 8x_4^4
211 6 2x_1^8x_2^4 + 2x_2^8 + 4x_4^4
1111 1 8x_2^8

Crossrefs

Cf. A337952 (oriented), A128767 (unoriented), A337954 (chiral).
Other elements: A331361 (tesseract edges, hyperoctahedron faces), A331357 (tesseract faces, hyperoctahedron edges), A337958 (tesseract facets, hyperoctahedron vertices).
Other polychora: A132366(n-1) (4-simplex facets/vertices), A338951 (24-cell), A338967 (120-cell, 600-cell).
Row 4 of A325015 (orthoplex facets, orthotope vertices).

Programs

  • Mathematica
    Table[(3n^12+5n^8+12n^6+28n^4)/48,{n,30}]

Formula

a(n) = n^4 * (3*n^8 + 5*n^4 + 12*n^2 + 28) / 48.
a(n) = 1*C(n,1) + 306*C(n,2) + 33207*C(n,3) + 921908*C(n,4) + 10359075*C(n,5) + 59584470*C(n,6) + 197644440*C(n,7) + 400752240*C(n,8) + 505197000*C(n,9) + 386694000*C(n,10) + 164656800*C(n,11) + 29937600*C(n,12), where the coefficient of C(n,k) is the number of achiral colorings using exactly k colors.
a(n) = 2*A128767(n) - A337952(n) = A337952(n) - 2*A337954(n) = A128767(n) - A337954(n).

A337956 Number of oriented colorings of the 8 cubic facets of a tesseract or of the 8 vertices of a hyperoctahedron.

Original entry on oeis.org

1, 15, 126, 730, 3270, 11991, 37450, 102726, 253485, 573265, 1205556, 2384460, 4475926, 8031765, 13858860, 23106196, 37372545, 58837851, 90421570, 135971430, 200486286, 290376955, 413769126, 580852650, 804281725
Offset: 1

Views

Author

Robert A. Russell, Oct 03 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. The Schläfli symbols for the tesseract and the hyperoctahedron are {4,3,3} and {3,3,4} respectively. Both figures are regular 4-D polyhedra and they are mutually dual.

Crossrefs

Cf. A337957 (unoriented), A234249(n+1) (chiral), A337958 (achiral).
Other elements: A331354 (hyperoctahedron edges, tesseract faces), A331358 (hyperoctahedron faces, tesseract edges), A337952 (hyperoctahedron facets, tesseract vertices).
Other polychora: A337895 (5-cell), A338948 (24-cell), A338964 (120-cell, 600-cell).
Row 4 of A325004 (orthotope facets, orthoplex vertices).

Programs

  • Mathematica
    Table[Binomial[Binomial[n+1,2]+3,4] + Binomial[Binomial[n,2],4],{n,30}]

Formula

a(n) = binomial(binomial(n+1,2)+3,4) + binomial(binomial(n,2),4).
a(n) = n * (n+1) * (n^6 - n^5 + 7*n^4 + 29*n^3 + 16*n^2 - 4*n + 48) / 192.
a(n) = 1*C(n,1) + 13*C(n,2) + 84*C(n,3) + 312*C(n,4) + 735*C(n,5) + 1020*C(n,6) + 735*C(n,7) + 210*C(n,8), where the coefficient of C(n,k) is the number of oriented colorings using exactly k colors.
a(n) = A337957(n) + A234249(n+1) = 2*A337957(n) - A337958(n) = 2*A234249(n+1) + A337958(n).
From Stefano Spezia, Oct 04 2020: (Start)
G.f.: x*(1 + 6*x + 27*x^2 + 52*x^3 + 102*x^4 + 21*x^5 + x^6)/(1 - x)^9.
a(n) = 9*a(n-1)-36*a(n-2)+84*a(n-3)-126*a(n-4)+126*a(n-5)-84*a(n-6)+36*a(n-7)-9*a(n-8)+a(n-8) for n > 8.
(End)

A338980 Number of oriented colorings of the 120 dodecahedral facets of the 4-D 120-cell (or 120 vertices of the 4-D 600-cell) using exactly n colors.

Original entry on oeis.org

0, 1, 184614999414571937405905419562270, 249584763877004334779054488506782340719383629107224173, 245395425663663491880846922641400894840783985813370231599231766603156
Offset: 0

Views

Author

Robert A. Russell, Dec 13 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. The Schläfli symbols of the 120-cell and 600-cell are {5,3,3} and {3,3,5} respectively. They are mutually dual. For n>120, a(n) = 0.
Sequences for other elements of the 120-cell and 600-cell are not suitable for the OEIS as the first significant datum is too big. We provide generating functions here using bp(j) = Sum_{k=1..j} k! * S2(j,k) * x^k.
For the 600 facets of the 600-cell (vertices of the 120-cell), the generating function is 2*bp(20)/15 + bp(30)/5 + 2*bp(40)/15 + bp(50)/6 + 13*bp(60)/150 + bp(100)/180 + bp(104)/18 + 13*bp(120)/150 + bp(150)/120 + bp(200)/180 + bp(208)/18 + bp(300)/7200 + bp(302)/16 + bp(600)/7200.
For the 720 pentagonal faces of the 120-cell (edges of the 600-cell), the generating function is 2*bp(24)/15 + bp(36)/5 + 2*bp(48)/15 + bp(60)/6 + 7*bp(72)/150 + bp(76)/25 + 11*bp(120)/180 + 7*bp(144)/150 + bp(152)/25 + bp(180)/120 + 11*bp(240)/180 + bp(360)/7200 + bp(364)/16 + bp(720)/7200.
For the 1200 edges of the 120-cell (triangular faces of the 600-cell), the generating function is 2*bp(40)/15 + bp(60)/5 + 2*bp(80)/15 + bp(100)/6 + 13*bp(120)/150 + bp(200)/180 + bp(202)/18 + 13*bp(240)/150 + bp(300)/120 + bp(400)/180 + bp(404)/18 + bp(600)/7200 + bp(604)/16 + bp(1200)/7200.

Crossrefs

Cf. A338981 (unoriented), A338982 (chiral), A338983 (achiral), A338964 (up to n colors), A337895 (5-cell), A337952 (8-cell vertices, 16-cell facets), A337956 (16-cell vertices, 8-cell facets), A338948 (24-cell).

Programs

  • Mathematica
    bp[j_] := Sum[k! StirlingS2[j, k] x^k, {k, j}] (*binomial series*)
    CoefficientList[2bp[4]/15+bp[6]/5+2bp[8]/15+bp[10]/6+7bp[12]/150+bp[16]/25+bp[20]/180+bp[22]/18+7bp[24]/150+bp[30]/120+bp[32]/25+bp[40]/180+bp[44]/18+bp[60]/7200+bp[62]/16+bp[120]/7200,x]

Formula

A338964(n) = Sum_{j=1..Min(n,120)} a(n) * binomial(n,j).
a(n) = A338981(n) + A338982(n) = 2*A338981(n) - A338983(n) = 2*A338982(n) + A338983(n).
G.f.: 2*bp(4)/15 + bp(6)/5 + 2*bp(8)/15 + bp(10)/6 + 7*bp(12)/150 + bp(16)/25 + bp(20)/180 + bp(22)/18 + 7*bp(24)/150 + bp(30)/120 + bp(32)/25 + bp(40)/180 + bp(44)/18 + bp(60)/7200 + bp(62)/16 + bp(120)/7200, where bp(j) = Sum_{k=1..j} k! * S2(j,k) * x^k and S2(j,k) is the Stirling subset number, A008277.
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