96338domain: NAppears in sequencesNumber of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w+x+y>0.at n=29A211545a(n) = Sum_{k=0..floor(n/2)} (-1)^k * binomial(n-1-k,n-2*k) * binomial(2*k,k).at n=19A360313Expansion of g.f. A(x) satisfying A(x) = (1 + 2*x*A(x)) * (1 + 3*x*A(x)^2).at n=5A375436