A367957 a(n) = Product_{i=1..n, j=1..n} (i + 4*j).

1, 5, 2700, 567567000, 101370917007360000, 26995322179162164731904000000, 16635639072295355604762223305031680000000000, 34026881962001914598329145027742925521204742717440000000000000

Offset

0,2

Links

Table of n, a(n) for n=0..7.

Formula

a(n) ~ A^(1/4) * 5^(25*n*(n+1)/8 + 29/48) * n^(n^2 - 29/48) / (Pi^(1/4) * Gamma(1/4)^(1/2) * 2^(n*(4*n+5) + 5/6) * exp(3*n^2/2 + 1/48)), where A = A074962 is the Glaisher-Kinkelin constant.

Mathematica

Table[Product[i + 4*j, {i, 1, n}, {j, 1, n}], {n, 0, 10}]

Crossrefs

Cf. A074962, A079478, A324402, A367956, A367958.

Sequence in context: A114716 A036772 A117011 * A274527 A258980 A096934

Adjacent sequences: A367954 A367955 A367956 * A367958 A367959 A367960

Keyword

nonn

Author

Vaclav Kotesovec, Dec 06 2023

Status

approved