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A324438 a(n) = Product_{i=1..n, j=1..n} (i^5 + j^5). 5
2, 139392, 305013568273920000, 1174837791623127613548781790822400000000, 139642003782073074626249921818187528362524804267528306032640000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..5.

FORMULA

a(n) ~ c * 2^(2*n*(n+1)) * phi^(sqrt(5)*n*(n+1)) * exp(Pi*sqrt(phi)*n*(n+1)/5^(1/4) - 15*n^2/2) * n^(5*n^2 - 5/4), where phi = A001622 = (1+sqrt(5))/2 is the golden ratio and c = 0.1574073828647726237455544898360432469056972905505624900871695...

MATHEMATICA

Table[Product[i^5 + j^5, {i, 1, n}, {j, 1, n}], {n, 1, 6}]

CROSSREFS

Cf. A079478, A324403, A324426, A324437, A324439, A324440.

Sequence in context: A319022 A003840 A122540 * A167518 A178168 A271669

Adjacent sequences:  A324435 A324436 A324437 * A324439 A324440 A324441

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, Feb 28 2019

STATUS

approved

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Last modified November 30 05:12 EST 2021. Contains 349419 sequences. (Running on oeis4.)