login
A391633
Triangle read by rows: T(n,k) = Sum_{j=0..k} (-1)^(k-j) * binomial(k,j) * (4+j)^n.
2
1, 4, 1, 16, 9, 2, 64, 61, 30, 6, 256, 369, 302, 132, 24, 1024, 2101, 2550, 1830, 720, 120, 4096, 11529, 19502, 20460, 13080, 4680, 720, 16384, 61741, 140070, 201726, 186480, 107520, 35280, 5040, 65536, 325089, 963902, 1832292, 2298744, 1900080, 997920, 302400, 40320
OFFSET
0,2
LINKS
José L. Cereceda, Sums of powers of integers and generalized Stirling numbers of the second kind, arXiv:2211.11648 [math.NT], 2022.
Donald E. Knuth, Johann Faulhaber and Sums of Powers, arXiv:math/9207222 [math.CA], 1992.
Petro Kolosov, Formulas for Sums of Powers, GitHub, 2025.
Petro Kolosov, Mathematica programs, GitHub, 2025.
FORMULA
Let F(t, n, k) = Sum_{j=0..k} (-1)^(k-j) * binomial(k,j) * (t+j)^n, then
F(0, n, k) = A131689(n,k),
F(1, n, k) = A028246(n-1,k-1),
F(2, n, k) = A038719(n,k),
F(3, n, k) = A391552(n,k),
F(4, n, k) = T(n,k) (this sequence),
F(5, n, k) = A391635(n,k).
T(n,k) = Sum_{j=0..n} binomial(4,j)*Stirling2(n,k+j)*(k+j)!.
Let S_m(n) be a sum of powers: S_m(n) = 1^m + 2^m + 3^m + ... + n^m, then
S_m(n) = Sum_{j=0..m} T(m,j) * ( C(n-3,j+1) + (-1)^j*C(j+3,j+1) ).
EXAMPLE
Triangle begins:
k= 0 1 2 3 4 5 6 7
---------------------------------------------------------------
n=0: 1;
n=1: 4, 1;
n=2: 16, 9, 2;
n=3: 64, 61, 30, 6;
n=4: 256, 369, 302, 132, 24;
n=5: 1024, 2101, 2550, 1830, 720, 120;
n=6: 4096, 11529, 19502, 20460, 13080, 4680, 720;
n=7: 16384, 61741, 140070, 201726, 186480, 107520, 35280, 5040;
...
MATHEMATICA
(* Prints the values of T(n, k) as triangle. *)
T[t_, n_, k_] := Sum[(-1)^(k - j)*Binomial[k, j]*(t + j)^n, {j, 0, n}];
Column[Table[T[4, n, k], {n, 0, 10}, {k, 0, n}]]
(* The formula in terms of Stirling2 numbers. *)
T2[t_, n_, k_] := Sum[Binomial[t, j]* StirlingS2[n, k + j]*(k + j)!, {j, 0, n}];
Column[Table[T2[4, n, k], {n, 0, 10}, {k, 0, n}]]
KEYWORD
nonn,tabl,easy
AUTHOR
Petro Kolosov, Dec 14 2025
STATUS
approved