OFFSET
1,1
FORMULA
Equals limit n->infinity (Product_{k=0..n} (k^2)!) / (n^((2*n + 1)*(2*n^2 + 2*n + 3)/6) * (2*Pi)^(n/2) / exp(5*n^3/9 + n^2/2 + n)).
Equals sqrt(2*Pi) * exp(Zeta(3)/(2*Pi^2)) * Product_{n>=1} ((n^2)!/stirling(n^2)), where stirling(n^2) = sqrt(2*Pi) * n^(2*n^2+1) / exp(n^2) is the Stirling approximation of (n^2)!. - Vaclav Kotesovec, Apr 20 2016
EXAMPLE
3.048330306522348566911920417337613015885313475689049184525483697684834...
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Vaclav Kotesovec, Feb 24 2015
STATUS
approved