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A324440 a(n) = Product_{i=1..n, j=1..n} (i^7 + j^7). 5
2, 8520192, 956147263254051187507200, 790929096572487518050439299107158612099228070051840000, 266108022587896795750359251172229660295854509829286134803404773931312693787460334360985600000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Limit_{n->infinity} (a(n)^(1/n^2))/n^7 = 2^(3/2) * (cos(3*Pi/14) / tan(Pi/7))^sin(3*Pi/14) / ((cos(Pi/14)*tan(3*Pi/14))^sin(Pi/14) * (sin(Pi/7)*tan(Pi/14))^cos(Pi/7)) * exp((Pi/sin(Pi/7) - 21)/2) = 0.0334234967249533921390751418772468470887965377...

MATHEMATICA

Table[Product[i^7+j^7, {i, 1, n}, {j, 1, n}], {n, 1, 6}]

CROSSREFS

Cf. A079478, A324403, A324426, A324437, A324438, A324439.

Sequence in context: A157991 A233555 A273729 * A121390 A170997 A326615

Adjacent sequences:  A324437 A324438 A324439 * A324441 A324442 A324443

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, Feb 28 2019

STATUS

approved

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Last modified December 2 10:24 EST 2021. Contains 349437 sequences. (Running on oeis4.)