392502domain: NAppears in sequencesSquarefree n such that the elliptic curve n*y^2 = x^3 - x arising in the "congruent number" problem has rank 3 and nontrivial SHA[2].at n=21A062694a(n) = (n^2 + 1)*(n^2 + 2).at n=25A304579Number of ordered pairs of distinct integer partitions of n.at n=20A355390