135916002domain: NAppears in sequencesCoordination sequence for A_9 lattice.at n=10A008393Number of integer sequences of length n+1 with sum zero and sum of absolute values 20.at n=8A157059a(0) = 0, a(n) = [x^n] P(n-1,(1 + x)/(1 - x)) for n >= 1, where P(n,x) denotes the n-th Legendre polynomial.at n=10A352654