1074934domain: NAppears in sequencesTriangle, read by rows, where g.f.: A(x,y) = exp( Sum_{n>=1} (2^n + y)^n * x^n/n ) is a power series in x and y with integer coefficients.at n=16A155810a(n) = [x^(n+1)*y] exp( Sum_{m>=1} (2^m + y)^m * x^m/m ), in which the coefficients of x^n*y^k are integer for n>=k>=0.at n=4A155811