36135domain: NAppears in sequencesa(n) = (n-1)*(n+2)*(2*n+11)/2.at n=30A130862Total number of congruence subgroups of PSL(2,Z) of genus n.at n=22A258691Numbers k such that phi(x) = 12*k+2 is solvable, where phi is Euler's totient A000010.at n=33A289364G.f. A(x) satisfies A(x) = ( 1 + x/(1 - x*A(x)^(3/4)) )^4.at n=8A378858