243928domain: NAppears in sequencesG.f.: sqrt(1 + 2*Sum_{n>=1} 2^n*x^(n^2)).at n=13A227315T(n, k) = Sum_{j=k..n} binomial(n, j)*E2(j, j-k), where E2 are the Eulerian numbers A201637. Triangle read by rows, T(n, k) for 0 <= k <= n.at n=41A343804