A256016
a(n) = n! * Sum_{k=0..n} k^n/k!.
Original entry on oeis.org
1, 1, 6, 57, 796, 15145, 374526, 11669665, 447595800, 20733553809, 1141067915290, 73552752257281, 5484203261135028, 467864288815609465, 45236104846954021014, 4915818294874879570305, 596044703812665607374256, 80118478395137652912476449, 11870487496575403846760198322
Offset: 0
-
Join[{1}, Table[n!*Sum[k^n/k!,{k,0,n}],{n,1,20}]]
-
a(n) = n!*sum(k=0, n, k^n/k!); \\ Michel Marcus, Aug 15 2020
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my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k*x)^k/(k!*(1-k*x))))) \\ Seiichi Manyama, Aug 23 2022
A337002
a(n) = n! * Sum_{k=0..n} k^4 / k!.
Original entry on oeis.org
0, 1, 18, 135, 796, 4605, 28926, 204883, 1643160, 14795001, 147960010, 1627574751, 19530917748, 253901959285, 3554627468406, 53319412076715, 853110593292976, 14502880086064113, 261051841549259010, 4959984989436051511, 99199699788721190220
Offset: 0
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Table[n! Sum[k^4/k!, {k, 0, n}], {n, 0, 20}]
nmax = 20; CoefficientList[Series[x (1 + 7 x + 6 x^2 + x^3) Exp[x]/(1 - x), {x, 0, nmax}], x] Range[0, nmax]!
a[0] = 0; a[n_] := a[n] = n (n^3 + a[n - 1]); Table[a[n], {n, 0, 20}]
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a(n) = n! * sum(k=0, n, k^4/k!); \\ Michel Marcus, Aug 12 2020
A337085
Square array T(n,k), n>=0, k>=0, read by antidiagonals, where T(n,k) = n! * Sum_{j=0..n} j^k/j!.
Original entry on oeis.org
1, 0, 2, 0, 1, 5, 0, 1, 4, 16, 0, 1, 6, 15, 65, 0, 1, 10, 27, 64, 326, 0, 1, 18, 57, 124, 325, 1957, 0, 1, 34, 135, 292, 645, 1956, 13700, 0, 1, 66, 345, 796, 1585, 3906, 13699, 109601, 0, 1, 130, 927, 2404, 4605, 9726, 27391, 109600, 986410, 0, 1, 258, 2577, 7804, 15145, 28926, 68425, 219192, 986409, 9864101
Offset: 0
Square array begins:
1, 0, 0, 0, 0, 0, 0, ...
2, 1, 1, 1, 1, 1, 1, ...
5, 4, 6, 10, 18, 34, 66, ...
16, 15, 27, 57, 135, 345, 927, ...
65, 64, 124, 292, 796, 2404, 7804, ...
326, 325, 645, 1585, 4605, 15145, 54645, ...
1957, 1956, 3906, 9726, 28926, 98646, 374526, ...
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T[n_, k_] := n! * Sum[If[j == k == 0, 1, j^k]/j!, {j, 0, n}]; Table[T[k, n-k], {n, 0, 9}, {k, 0, n}] // Flatten (* Amiram Eldar, Apr 29 2021 *)
A368574
a(n) = n! * Sum_{k=0..n} binomial(k+2,3) / k!.
Original entry on oeis.org
0, 1, 6, 28, 132, 695, 4226, 29666, 237448, 2137197, 21372190, 235094376, 2821132876, 36674727843, 513446190362, 7701692856110, 123227085698576, 2094860456876761, 37707488223782838, 716442276251875252, 14328845525037506580, 300905756025787639951, 6619926632567328080946
Offset: 0
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my(N=30, x='x+O('x^N)); concat(0, Vec(serlaplace(x*sum(k=0, 2, binomial(2, k)*x^k/(k+1)!)*exp(x)/(1-x))))
A356688
a(n) = n! * Sum_{k=0..n} k^(3*n)/k!.
Original entry on oeis.org
1, 1, 66, 21225, 18952156, 36175231585, 126556309395486, 733064060959310689, 6540867625730306094360, 85180334386943946887707617, 1552697061493449955344530003290, 38315904135534199560725372265381721, 1245605749857294018587318829355458646068
Offset: 0
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a[n_] := n! * Sum[k^(3*n)/k!, {k, 0, n}]; a[0] = 1; Array[a, 13, 0] (* Amiram Eldar, Aug 23 2022 *)
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a(n) = n!*sum(k=0, n, k^(3*n)/k!);
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my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k^3*x)^k/(k!*(1-k^3*x)))))
A121682
Triangle read by rows: T(i,j) = (T(i-1,j) + i)*i.
Original entry on oeis.org
1, 6, 4, 27, 21, 9, 124, 100, 52, 16, 645, 525, 285, 105, 25, 3906, 3186, 1746, 666, 186, 36, 27391, 22351, 12271, 4711, 1351, 301, 49, 219192, 178872, 98232, 37752, 10872, 2472, 456, 64, 1972809, 1609929, 884169, 339849, 97929, 22329, 4185, 657, 81, 19728190, 16099390, 8841790, 3398590, 979390, 223390, 41950, 6670, 910, 100
Offset: 1
Triangle begins:
1
6 4
27 21 9
124 100 52 16
645 525 285 105 25
3906 3186 1746 666 186 36
27391 22351 12271 4711 1351 301 49
...
- T. A. Gulliver, Sequences from Cubes of Integers, Int. Math. Journal, 4 (2003), 439-445.
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T:= proc(i, j) option remember;
`if`(j<1 or j>i, 0, (T(i-1, j)+i)*i)
end:
seq(seq(T(n, k), k=1..n), n=1..10); # Alois P. Heinz, Jun 22 2022
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T[n_, k_] /; 1 <= k <= n := T[n, k] = (T[n-1, k]+n)*n;
T[, ] = 0;
Table[T[n, k], {n, 1, 10}, {k, 1, n}] // Flatten (* Jean-François Alcover, Nov 17 2022 *)
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def T(i, j): return (T(i-1, j)+i)*i if 1 <= j <= i else 0
print([T(r, c) for r in range(1, 11) for c in range(1, r+1)]) # Michael S. Branicky, Jun 22 2022
A368716
a(n) = n! * Sum_{k=0..n} (-1)^(n-k) * k^3 / k!.
Original entry on oeis.org
0, 1, 6, 9, 28, -15, 306, -1799, 14904, -133407, 1335070, -14684439, 176214996, -2290792751, 32071101258, -481066515495, 7697064252016, -130850092279359, 2355301661034294, -44750731559644727, 895014631192902540, -18795307255050944079
Offset: 0
-
f:= proc(n) option remember;
- n*procname(n-1)+n^3
end proc:
f(0):= 0:
seq(f(i),i=0..30); # Robert Israel, May 13 2025
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Table[n + n^2 + (-1)^n*n*Subfactorial[n-1], {n, 0, 20}] (* Vaclav Kotesovec, Jul 18 2025 *)
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my(N=30, x='x+O('x^N)); concat(0, Vec(serlaplace(sum(k=0, 3, stirling(3, k, 2)*x^k)*exp(x)/(1+x))))
A368760
a(n) = n! * (1 + Sum_{k=0..n} k^3 / k!).
Original entry on oeis.org
1, 2, 12, 63, 316, 1705, 10446, 73465, 588232, 5294817, 52949170, 582442201, 6989308140, 90861008017, 1272054114982, 19080811728105, 305292987653776, 5189980790119105, 93419654222149722, 1774973430220851577, 35499468604417039540, 745488840692757839601
Offset: 0
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my(N=30, x='x+O('x^N)); Vec(serlaplace((1+sum(k=0, 3, stirling(3, k, 2)*x^k)*exp(x))/(1-x)))
A374844
a(n) = n! * Sum_{k=1..n} k^k / k!.
Original entry on oeis.org
0, 1, 6, 45, 436, 5305, 78486, 1372945, 27760776, 637267473, 16372674730, 465411092641, 14501033559948, 491388542871577, 17991446425760094, 707765586767260785, 29770993461985724176, 1333347150740094075169, 63346656788618230928466
Offset: 0
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a:= proc(n) a(n):= n*a(n-1) + n^n end: a(0):= 0:
seq(a(n), n=0..23); # Alois P. Heinz, Jul 22 2024
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a(n) = n!*sum(k=1, n, k^k/k!);
Showing 1-9 of 9 results.
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