601528domain: NAppears in sequencesTheta series of E_8 lattice with respect to midpoint of edge.at n=33A045819Expansion of Product_{k>=1} 1/(1 - 2*x^(k^2)).at n=19A291583Largest even k such that h(-k) = 2n, where h(D) is the class number of the quadratic field with discriminant D; or 0 if no such k exists.at n=43A357573