A346740
Expansion of e.g.f.: exp(exp(x) - 5*x - 1).
Original entry on oeis.org
1, -4, 17, -75, 340, -1573, 7393, -35178, 169035, -818603, 3989250, -19538555, 96084397, -474052868, 2344993157, -11624422855, 57722000172, -287012948441, 1428705217949, -7118044107698, 35489117143047, -177036294035559, 883588566571138, -4411213326568599, 22032317835916969
Offset: 0
-
R:=PowerSeriesRing(Rationals(), 30);
Coefficients(R!(Laplace( Exp(Exp(x) -5*x -1) ))) // G. C. Greubel, Jun 12 2024
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nmax = 24; CoefficientList[Series[Exp[Exp[x] - 5 x - 1], {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[Binomial[n, k] (-5)^(n - k) BellB[k], {k, 0, n}], {n, 0, 24}]
a[0] = 1; a[n_] := a[n] = -5 a[n - 1] + Sum[Binomial[n - 1, k] a[k], {k, 0, n - 1}]; Table[a[n], {n, 0, 24}]
-
[factorial(n)*( exp(exp(x) -5*x -1) ).series(x, n+1).list()[n] for n in (0..30)] # G. C. Greubel, Jun 12 2024
A102286
Total number of odd blocks in all partitions of n-set.
Original entry on oeis.org
1, 2, 7, 24, 96, 418, 1989, 10216, 56275, 330424, 2057672, 13532060, 93633021, 679473694, 5156626991, 40824399712, 336406367196, 2879570703510, 25557841113625, 234822774979908, 2230107923204443, 21861817965483016, 220940261740238140, 2299258336094622008
Offset: 1
a(3)=7 because we have (123), (1)/23, 12/(3), 13/(2), (1)/(2)/(3); the odd blocks are shown between parentheses.
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G:=sinh(x)*exp(exp(x)-1): Gser:=series(G,x=0,30): seq(n!*coeff(Gser,x^n),n=1..25); # Emeric Deutsch
# second Maple program:
with(combinat):
b:= proc(n, i) option remember; `if`(n=0 or i=1, [1, n],
add((p->(p+[0, `if`(i::odd, j, 0)*p[1]]))(
b(n-i*j, i-1))*multinomial(n, n-i*j, i$j)/j!, j=0..n/i))
end:
a:= n-> b(n$2)[2]:
seq(a(n), n=1..30); # Alois P. Heinz, Sep 16 2015
-
Range[0, nn]! CoefficientList[
D[Series[Exp[ (Cosh[x] - 1) + y Sinh[x]], {x, 0, nn}], y] /. y -> 1, x] (* Geoffrey Critzer, Aug 28 2012 *)
With[{nn=30},CoefficientList[Series[Sinh[x]Exp[Exp[x]-1],{x,0,nn}],x] Range[0,nn]!] (* Harvey P. Dale, Jul 03 2021 *)
A261137
Number of set partitions B'_t(n) of {1,2,...,t} into at most n parts, so that no part contains both 1 and t, or both i and i+1 with 1 <= i < t; triangle B'_t(n), t>=0, 0<=n<=t, read by rows.
Original entry on oeis.org
1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 3, 4, 0, 0, 0, 5, 10, 11, 0, 0, 1, 11, 31, 40, 41, 0, 0, 0, 21, 91, 147, 161, 162, 0, 0, 1, 43, 274, 568, 694, 714, 715, 0, 0, 0, 85, 820, 2227, 3151, 3397, 3424, 3425, 0, 0, 1, 171, 2461, 8824, 14851, 17251, 17686, 17721, 17722
Offset: 0
Triangle starts:
1;
0, 0;
0, 0, 1;
0, 0, 0, 1;
0, 0, 1, 3, 4;
0, 0, 0, 5, 10, 11;
0, 0, 1, 11, 31, 40, 41;
0, 0, 0, 21, 91, 147, 161, 162;
0, 0, 1, 43, 274, 568, 694, 714, 715;
0, 0, 0, 85, 820, 2227, 3151, 3397, 3424, 3425;
...
- Alois P. Heinz, Rows n = 0..140, flattened
- John R. Britnell and Mark Wildon, Bell numbers, partition moves and the eigenvalues of the random-to-top shuffle in Dynkin Types A, B and D, arXiv:1507.04803 [math.CO], 2015.
- D. E. Knuth and O. P. Lossers, Partitions of a circular set, Problem 11151 in Amer. Math. Monthly 114 (3), (2007), p 265, E_4.
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g:= proc(t, l, h) option remember; `if`(t=0, `if`(l=1, 0, x^h),
add(`if`(j=l, 0, g(t-1, j, max(h,j))), j=1..h+1))
end:
B:= t-> (p-> seq(add(coeff(p, x, j), j=0..i), i=0..t))(g(t, 0$2)):
seq(B(t), t=0..12); # Alois P. Heinz, Aug 10 2015
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StirPrimedGF[0, x_] := 1; StirPrimedGF[1, x_] := 0;
StirPrimedGF[n_, x_] := x^n/(1 + x)*Product[1/(1 - j*x), {j, 1, n - 1}];
StirPrimed[0, 0] := 1; StirPrimed[0, _] := 0;
StirPrimed[t_, n_] := Coefficient[Series[StirPrimedGF[n, x], {x, 0, t}], x^t];
BPrimed[t_, n_] := Sum[StirPrimed[t, m], {m, 0, n}]
(* Second program: *)
g[t_, l_, h_] := g[t, l, h] = If[t == 0, If[l == 1, 0, x^h], Sum[If[j == l, 0, g[t - 1, j, Max[h, j]]], {j, 1, h + 1}]];
B[t_] := Function[p, Table[Sum[Coefficient[p, x, j], {j, 0, i}], {i, 0, t}] ][g[t, 0, 0]];
Table[B[t], {t, 0, 12}] // Flatten (* Jean-François Alcover, May 20 2016, after Alois P. Heinz *)
A306357
Number of nonempty subsets of {1, ..., n} containing no three cyclically successive elements.
Original entry on oeis.org
0, 1, 3, 6, 10, 20, 38, 70, 130, 240, 442, 814, 1498, 2756, 5070, 9326, 17154, 31552, 58034, 106742, 196330, 361108, 664182, 1221622, 2246914, 4132720, 7601258, 13980894, 25714874, 47297028, 86992798, 160004702, 294294530, 541292032, 995591266, 1831177830
Offset: 0
The a(1) = 1 through a(5) = 20 stable subsets:
{1} {1} {1} {1} {1}
{2} {2} {2} {2}
{1,2} {3} {3} {3}
{1,2} {4} {4}
{1,3} {1,2} {5}
{2,3} {1,3} {1,2}
{1,4} {1,3}
{2,3} {1,4}
{2,4} {1,5}
{3,4} {2,3}
{2,4}
{2,5}
{3,4}
{3,5}
{4,5}
{1,2,4}
{1,3,4}
{1,3,5}
{2,3,5}
{2,4,5}
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stabsubs[g_]:=Select[Rest[Subsets[Union@@g]],Select[g,Function[ed,UnsameQ@@ed&&Complement[ed,#]=={}]]=={}&];
Table[Length[stabsubs[Partition[Range[n],3,1,1]]],{n,15}]
A324014
Number of self-complementary set partitions of {1, ..., n} with no cyclical adjacencies (successive elements in the same block, where 1 is a successor of n).
Original entry on oeis.org
1, 0, 1, 1, 2, 3, 9, 16, 43, 89, 250, 571, 1639
Offset: 0
The a(3) = 1 through a(6) = 9 self-complementary set partitions with no cyclical adjacencies:
{{1}{2}{3}} {{13}{24}} {{14}{25}{3}} {{135}{246}}
{{1}{2}{3}{4}} {{1}{24}{3}{5}} {{13}{25}{46}}
{{1}{2}{3}{4}{5}} {{14}{25}{36}}
{{1}{24}{35}{6}}
{{13}{2}{46}{5}}
{{14}{2}{36}{5}}
{{15}{26}{3}{4}}
{{1}{25}{3}{4}{6}}
{{1}{2}{3}{4}{5}{6}}
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sps[{}]:={{}};sps[set:{i_,_}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,_}];
cmp[stn_]:=Union[Sort[Max@@Join@@stn+1-#]&/@stn];
Table[Select[sps[Range[n]],And[cmp[#]==Sort[#],Total[If[First[#]==1&&Last[#]==n,1,0]+Count[Subtract@@@Partition[#,2,1],-1]&/@#]==0]&]//Length,{n,0,10}]
A324015
Number of nonempty subsets of {1, ..., n} containing no two cyclically successive elements.
Original entry on oeis.org
0, 1, 2, 3, 6, 10, 17, 28, 46, 75, 122, 198, 321, 520, 842, 1363, 2206, 3570, 5777, 9348, 15126, 24475, 39602, 64078, 103681, 167760, 271442, 439203, 710646, 1149850, 1860497, 3010348, 4870846, 7881195, 12752042, 20633238, 33385281, 54018520, 87403802
Offset: 0
The a(6) = 17 stable subsets:
{1}, {2}, {3}, {4}, {5}, {6},
{1,3}, {1,4}, {1,5}, {2,4}, {2,5}, {2,6}, {3,5}, {3,6}, {4,6},
{1,3,5}, {2,4,6}.
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stabsubs[g_]:=Select[Rest[Subsets[Union@@g]],Select[g,Function[ed,UnsameQ@@ed&&Complement[ed,#]=={}]]=={}&];
Table[Length[stabsubs[Partition[Range[n],2,1,1]]],{n,0,10}]
A330605
a(n) = exp(-1) * Sum_{k>=0} (n*k - 1)^n / k!.
Original entry on oeis.org
1, 0, 5, 89, 2737, 121399, 7316101, 572218716, 56142822849, 6731180810945, 965898950508901, 163116461798211503, 31969444766902475185, 7187057932197297484108, 1834860441330563739401765, 527403671798720265634312349, 169396494914472404237224898305
Offset: 0
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Table[Exp[-1] Sum[(n k - 1)^n/k!, {k, 0, Infinity}], {n, 0, 16}]
Join[{1}, Table[Sum[(-1)^(n - k) Binomial[n, k] n^k BellB[k], {k, 0, n}], {n, 1, 16}]]
Table[n! SeriesCoefficient[Exp[Exp[n x] - x - 1], {x, 0, n}], {n, 0, 16}]
A337040
a(n) = exp(-1/4) * Sum_{k>=0} (4*k - 1)^n / (4^k * k!).
Original entry on oeis.org
1, 0, 4, 16, 112, 896, 8384, 88320, 1032448, 13242368, 184591360, 2773929984, 44641579008, 765196926976, 13905753980928, 266855007453184, 5388980396818432, 114172599765827584, 2530858142594760704, 58556990344729198592, 1411095950792925904896, 35347148031264582270976
Offset: 0
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nmax = 21; CoefficientList[Series[Exp[(Exp[4 x] - 1)/4 - x], {x, 0, nmax}], x] Range[0, nmax]!
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k] 4^k a[n - k - 1], {k, 1, n - 1}]; Table[a[n], {n, 0, 21}]
Table[Sum[(-1)^(n - k) Binomial[n, k] 4^k BellB[k, 1/4], {k, 0, n}], {n, 0, 21}]
A337041
a(n) = exp(-1/5) * Sum_{k>=0} (5*k - 1)^n / (5^k * k!).
Original entry on oeis.org
1, 0, 5, 25, 200, 1875, 20625, 256250, 3534375, 53515625, 881468750, 15667578125, 298478828125, 6060493750000, 130542772265625, 2971013486328125, 71193375156250000, 1790666151318359375, 47145509926611328125, 1296156682961425781250, 37129279010879638671875
Offset: 0
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nmax = 20; CoefficientList[Series[Exp[(Exp[5 x] - 1)/5 - x], {x, 0, nmax}], x] Range[0, nmax]!
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k] 5^k a[n - k - 1], {k, 1, n - 1}]; Table[a[n], {n, 0, 20}]
Table[Sum[(-1)^(n - k) Binomial[n, k] 5^k BellB[k, 1/5], {k, 0, n}], {n, 0, 20}]
A337042
a(n) = exp(-1/6) * Sum_{k>=0} (6*k - 1)^n / (6^k * k!).
Original entry on oeis.org
1, 0, 6, 36, 324, 3456, 43416, 618192, 9778320, 169827840, 3210376032, 65540155968, 1435094563392, 33510354739200, 830486180748672, 21756166766173440, 600339119317643520, 17394883290643709952, 527782830161632077312, 16727350847049194775552
Offset: 0
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nmax = 19; CoefficientList[Series[Exp[(Exp[6 x] - 1)/6 - x], {x, 0, nmax}], x] Range[0, nmax]!
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k] 6^k a[n - k - 1], {k, 1, n - 1}]; Table[a[n], {n, 0, 19}]
Table[Sum[(-1)^(n - k) Binomial[n, k] 6^k BellB[k, 1/6], {k, 0, n}], {n, 0, 19}]
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