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A203229
(n-1)-st elementary symmetric function of (1,16,...,n^4).
7
1, 17, 1393, 357904, 224021776, 290539581696, 697854274212096, 2859056348455305216, 18760911610508623282176, 187626456226399005573120000, 2747212346823835568109649920000, 56968733990900457398848318341120000, 1627136655389966817590114762694328320000
OFFSET
1,2
FORMULA
a(n) ~ 2 * Pi^6 * n^(4*n+2) / (45*exp(4*n)). - Vaclav Kotesovec, Aug 27 2017
Sum_{n>=1} a(n) * x^n / (n!)^4 = polylog(4,x) / (1 - x). - Ilya Gutkovskiy, Jul 14 2020
MATHEMATICA
f[k_] := k^4; t[n_] := Table[f[k], {k, 1, n}]
a[n_] := SymmetricPolynomial[n - 1, t[n]]
Table[a[n], {n, 1, 14}]
(* Alternative: *)
Table[(n!)^4 * Sum[1/i^4, {i, 1, n}], {n, 1, 20}] (* Vaclav Kotesovec, Aug 27 2017 *)
PROG
(Python)
from math import factorial
from sympy import harmonic
def A203229(n): return int(factorial(n)**4*harmonic(n, 4)) # Chai Wah Wu, May 08 2026
CROSSREFS
Column k=4 of A291556.
Sequence in context: A219562 A183236 A007410 * A269791 A256020 A072160
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Dec 30 2011
EXTENSIONS
a(13) from Chai Wah Wu, May 09 2026
STATUS
approved