G.f.: hypergeom([1/24, 5/24, 7/24, 11/24, 13/24, 17/24, 19/24, 23/24], [1/7, 2/7, 3/7, 1/2, 4/7, 5/7, 6/7], 570630428688384/823543*x).
a(n) = binomial(24*n,12*n)*binomial(12*n,4*n)*binomial(4*n,n)/(binomial(7*n,3*n)*binomial(2*n,n)). -
Chai Wah Wu, Feb 17 2026
a(n) ~ 2^(30*n-1) * 3^(12*n) / (7^(7*n+1/2) * sqrt(Pi*n)). -
Amiram Eldar, Feb 21 2026