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A291676
Main diagonal of A291656.
3
0, 1, 10, 3527, 123296356, 757031629267449, 1263498691933197473321646, 823340843273442113630752833831086703, 285062591046216676379736060856308430344065653125000
OFFSET
0,3
LINKS
FORMULA
a(n) = ((2n-1)!!)^n * Sum_{i=1..n} 1/(2*i-1)^n.
a(n) ~ 2^(n*(2*n + 1)/2) * n^(n^2) / exp(n^2 + 1/24). - Vaclav Kotesovec, Sep 25 2020
MATHEMATICA
Table[((2*n - 1)!!)^n * Sum[1/(2*k - 1)^n, {k, 1, n}], {n, 0, 10}] (* Vaclav Kotesovec, Sep 25 2020 *)
CROSSREFS
Sequence in context: A115481 A154238 A234144 * A249851 A024139 A320983
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 29 2017
STATUS
approved