12437880domain: NAppears in sequencesNumbers that can be expressed as the difference of the squares of primes in exactly eighteen distinct ways.at n=20A092014G.f.: 1/(1-x) = (1-x*y) * Sum_{k>=0} Sum_{n>=k} T(n,k)*x^n*y^k/(1+x)^(2^n-2^k).at n=37A172400G.f.: 1/(1-x) = Sum_{n>=0} a(n)*x^n/(1+x)^(2^(n+1)-2).at n=7A172402