88199domain: NAppears in sequences(Product of twin primes - 1)/2.at n=21A120876Triangle T(n,k) = 2*binomial(n,k)^2 - 1, read by rows, 0<=k<=n.at n=59A141597Triangle T(n,k) = 2*binomial(n,k)^2 - 1, read by rows, 0<=k<=n.at n=61A141597a(n) = 72*n^2 - 1.at n=34A158738