A061684
Generalized Bell numbers: column 3 of A275043.
Original entry on oeis.org
1, 1, 5, 64, 1613, 69026, 4566992, 437665649, 57903766797, 10193400044254, 2319001344297830, 665816738235745559, 236563125351122920088, 102303284135845463907107, 53093636013475924370369829, 32666276100771741793923209939, 23573762287735885858839134983437
Offset: 0
Probably
A061698 from the same paper is an erroneous version of this sequence. -
Les Reid, Jan 01 2011
-
b:= proc(n) option remember; `if`(n=0, 1,
add(b(n-i)*binomial(n-1, i-1)/i!^2, i=1..n))
end:
a:= n-> b(n)*n!^2:
seq(a(n), n=0..20); # Alois P. Heinz, May 11 2016
-
b[n_] := b[n] = If[n==0, 1, Sum[b[n-i]*Binomial[n-1, i-1]/i!^2, {i, 1, n}]];
a[n_] := b[n]*n!^2;
Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Mar 14 2017, after Alois P. Heinz *)
-
{a(n)=n!^3*polcoeff(exp(sum(m=1, n, x^m/m!^3)+x*O(x^n)), n)} /* Paul D. Hanna, Mar 15 2012 */
A061685
Generalized Bell numbers: column 4 of A275043.
Original entry on oeis.org
1, 1, 9, 298, 25097, 4383626, 1394519922, 738298190981, 608765840524809, 742996254490626106, 1289282092211451157634, 3078466688415490018129781, 9844321075186192301310239858, 41209705023068976933023104392293, 221473347301087557264532943397984133
Offset: 0
-
b:= proc(n) option remember; `if`(n=0, 1,
add(b(n-i)*binomial(n-1, i-1)/i!^3, i=1..n))
end:
a:= n-> b(n)*n!^3:
seq(a(n), n=0..20); # Alois P. Heinz, May 11 2016
-
b[n_] := b[n] = If[n==0, 1, Sum[b[n-i]*Binomial[n-1, i-1]/i!^3, {i, n}]];
a[n_] := b[n]*n!^3;
Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Mar 15 2017, after Alois P. Heinz *)
A061686
Generalized Bell numbers: column 5 of A275043.
Original entry on oeis.org
1, 1, 17, 1540, 461105, 350813126, 573843627152, 1797582928354025, 9904754169831094065, 89944005095677792967482, 1278494002506675052860358142, 27281796399886236251265603339575, 844252087185585895268923657508727440, 36800471170748991972750857754287551544147
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1,
add(binomial(n, k)^5*(n-k)*a(k)/n, k=0..n-1))
end:
seq(a(n), n=0..15); # Alois P. Heinz, Nov 07 2008
-
a[n_] := a[n] = If[n == 0, 1, Sum[Binomial[n, k]^5*(n-k)*a[k]/n, {k, 0, n-1}]]; Table[a[n], {n, 0, 15}] (* Jean-François Alcover, Mar 24 2014, after Alois P. Heinz *)
-
a61686=[1];A061686(n)={n>1||return(1);#a61686A061686(k))/n} \\ M. F. Hasler, May 11 2015
A061687
Generalized Bell numbers: column 6 of A275043.
Original entry on oeis.org
1, 1, 33, 8506, 9483041, 33056715626, 293327384637282, 5747475089121405893, 224054040415856117594913, 16044797009828490454609378642, 1981736776623437001042672440089658, 401147408702290404750740714717055504773, 127573929384655691416638350563783440408133922
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1,
add(binomial(n, k)^6*(n-k)*a(k)/n, k=0..n-1))
end:
seq(a(n), n=0..15); # Alois P. Heinz, Nov 07 2008
-
a[n_] := a[n] = If[n == 0, 1, Sum[Binomial[n, k]^6*(n-k)*a[k]/n, {k, 0, n-1}]]; Table[a[n], {n, 0, 15}] (* Jean-François Alcover, Mar 19 2014, after Alois P. Heinz *)
A061688
Generalized Bell numbers: column 7 of A275043.
Original entry on oeis.org
1, 1, 65, 48844, 209175233, 3464129078126, 173566857025139312, 22208366234650578141209, 6409515697874502425444186817, 3794729706423816704068204814925754, 4276126299841623727960390049367617509190, 8631647765438316626054238101611711249984175399
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1,
add(binomial(n, k)^7*(n-k)*a(k)/n, k=0..n-1))
end:
seq(a(n), n=0..12); # Alois P. Heinz, Nov 07 2008
-
a[n_] := a[n] = If[n == 0, 1, Sum[Binomial[n, k]^7*(n-k)*a[k]/n, {k, 0, n-1}]]; Table[a[n], {n, 0, 12}] (* Jean-François Alcover, Apr 17 2014, after Alois P. Heinz *)
A023998
Number of block permutations on an n-set which are uniform, i.e., corresponding blocks have same size.
Original entry on oeis.org
1, 1, 3, 16, 131, 1496, 22482, 426833, 9934563, 277006192, 9085194458, 345322038293, 15024619744202, 740552967629021, 40984758230303149, 2527342803112928081, 172490568947825135203, 12952575262915522547136, 1064521056888312620947794, 95305764621957309071404877
Offset: 0
Des FitzGerald (D.FitzGerald(AT)utas.edu.au)
For n=3 there are 25 block permutations, of which 9 of the form ({1} maps to {1,2}; {2,3} maps to {3}), are not uniform. Hence a(3) = 25 - 9 = 16.
Alternatively, for n=3 the 6 permutations of 3 cards produce 16 games, as follows: 123 -> {1,2,3}; 132 -> {1,32}, {1,3,2}; 213 -> {21,3}, {2,1,3}; 231 -> {21,3}, {2,31}, {2,3,1}; 312 -> {31,2}, {32,1}, {3,1,2}; 321 -> {321}, {32,1}, {31,2}, {3,21}, {3,2,1}.
G.f.: A(x) = 1 + x + 3*x^2/2!^2 + 16*x^3/3!^2 + 131*x^4/4!^2 + 1496*x^5/5!^2 + ...
log(A(x)) = x + x^2/2!^2 + x^3/3!^2 + x^4/4!^2 + x^5/5!^2 + ...
- Reinhard Zumkeller, Table of n, a(n) for n = 0..300
- M. Aguiar and R. C. Orellana, The Hopf algebra of uniform block permutations, J. Algebr. Comb. 28 (2008) 115-138
- D. Aldous and P. Diaconis, Longest increasing subsequences: from patience sorting to the Baik-Deift-Johansson theorem, Bull. Amer. Math. Soc. 36 (1999), 413-432.
- H. Cheballah, S. Giraudo, and R. Maurice, Combinatorial Hopf algebra structure on packed square matrices, arXiv preprint arXiv:1306.6605 [math.CO], 2013.
- Fabian Faulstich, Bernd Sturmfels, and Svala Sverrisdóttir, Algebraic Varieties in Quantum Chemistry, arXiv:2308.05258 [math.AG], 2023.
- D. G. FitzGerald and Jonathan Leech, Dual symmetric inverse monoids and representation theory, J. Australian Mathematical Society (Series A), Vol. 64 (1998), pp. 345-367.
- Raúl E. González-Torres, A geometric study of cores of idempotent stochastic matrices, Linear Algebra Appl. 527, 87-127 (2017).
- Rosa Orellana, Franco Saliola, Anne Schilling, and Mike Zabrocki, The lattice of submonoids of the uniform block permutations containing the symmetric group, arXiv:2405.09710 [math.CO], 2024. See p. 3.
- Sebastian Volz, Design and Implementation of Efficient Algorithms for Operations on Partitions of Sets, Bachelor Thesis, Saarland Univ. (Germany, 2023). See p. 45.
-
a023998 n = a023998_list !! n
a023998_list = 1 : f 2 [1] a132813_tabl where
f x ys (zs:zss) = y : f (x + 1) (ys ++ [y]) zss where
y = sum $ zipWith (*) ys zs
-- Reinhard Zumkeller, Apr 04 2014
-
b:= proc(n) option remember; `if`(n=0, 1,
add(b(n-i)*binomial(n-1, i-1)/i!, i=1..n))
end:
a:= n-> b(n)*n!:
seq(a(n), n=0..25); # Alois P. Heinz, May 11 2016
-
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k] Binomial[n-1, k] a[k], {k, 0, n-1}];
Array[a, 25, 0] (* Jean-François Alcover, Jul 28 2016 *)
nmax = 20; CoefficientList[Series[E^(-1 + BesselI[0, 2*Sqrt[x]]), {x, 0, nmax}], x]*Range[0, nmax]!^2 (* Vaclav Kotesovec, Jun 09 2019 *)
-
a(n)=if(n==0,1,sum(k=0,n-1,binomial(n,k)*binomial(n-1,k)*a(k))) \\ Paul D. Hanna, Aug 15 2007
-
{a(n)=n!^2*polcoeff(exp(sum(m=1, n, x^m/m!^2)+x*O(x^n)), n)} /* Paul D. Hanna */
-
N=66; x='x+O('x^N); /* that many terms */
Vec(serlaplace(serlaplace(exp(sum(n=1, N, x^n/n!^2))))) /* show terms */
/* Joerg Arndt, Jul 12 2011 */
-
v=vector(N); v[1]=1;
for (n=1,N-1, v[n+1]=sum(k=0,n-1, binomial(n,k)*binomial(n-1,k)*v[k+1]) );
v /* show terms */
/* Joerg Arndt, Jul 12 2011 */
A275044
Number of set partitions of [n^2] such that within each block the numbers of elements from all residue classes modulo n are equal for n>0, a(0)=1.
Original entry on oeis.org
1, 1, 3, 64, 25097, 350813126, 293327384637282, 22208366234650578141209, 213426677887357366350726096998529, 344735749788852590196707169431958672823413322, 118966637603805785518622376062965559343297730169187276656138
Offset: 0
a(2) = 3: 1234, 12|34, 14|23.
a(3) = 64: 123456789, 123456|789, 123459|678, 123468|579, ... , 159|267|348, 168|279|345, 189|267|345.
-
b:= proc(n, k) option remember; `if`(k*n=0, 1, add(
binomial(n, j)^k*(n-j)*b(j, k), j=0..n-1)/n)
end:
a:= n-> b(n$2):
seq(a(n), n=0..12);
-
b[n_, k_] := b[n, k] = If[k*n == 0, 1, Sum[Binomial[n, j]^k*(n-j)*b[j, k], {j, 0, n-1}]/n];
a[n_] := b[n, n];
Table[a[n], {n, 0, 12}] (* Jean-François Alcover, May 27 2018, translated from Maple *)
A275097
Number of set partitions of [8*n] such that within each block the numbers of elements from all residue classes modulo 8 are equal.
Original entry on oeis.org
1, 1, 129, 286498, 4802367617, 386652630390626, 112344305783644570242, 96703375432646667737903621, 213426677887357366350726096998529, 1081530653290057746718498987187644516546, 11534313393388449518393789691807687515711518754
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1, add(
binomial(n, j)^8*(n-j)*a(j), j=0..n-1)/n)
end:
seq(a(n), n=0..12);
A275098
Number of set partitions of [9*n] such that within each block the numbers of elements from all residue classes modulo 9 are equal.
Original entry on oeis.org
1, 1, 257, 1699300, 112660505345, 44687884101953126, 76502602935955053437072, 451167428778794282789329512425, 7771744024861563765933540267436016385, 344735749788852590196707169431958672823413322, 35650419033178479865362827431736721104304210986866382
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1, add(
binomial(n, j)^9*(n-j)*a(j), j=0..n-1)/n)
end:
seq(a(n), n=0..12);
A275099
Number of set partitions of [10*n] such that within each block the numbers of elements from all residue classes modulo 10 are equal.
Original entry on oeis.org
1, 1, 513, 10136746, 2672797504001, 5260857687009765626, 53531132944198868710856802, 2185249026716732313958375321948613, 297263694975439941710846391262298377605633, 116941828532092016226313310933885429108622288425362
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 1, add(
binomial(n, j)^10*(n-j)*a(j), j=0..n-1)/n)
end:
seq(a(n), n=0..12);
-
a[n_] := a[n] = If[n==0, 1, Sum[Binomial[n, j]^10*(n-j)*a[j], {j, 0, n-1}]/n];
Table[a[n], {n, 0, 12}] (* Jean-François Alcover, Jun 27 2022, after Alois P. Heinz *)
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