210944domain: NAppears in sequencesa(n) = 2a(n-2) + 4a(n-3), n >= 3.at n=22A134812Number of subsets of {1..n} containing the product of any set of distinct elements whose product is <= n.at n=19A326081Number of n X n (0,1)-matrices A over the reals such that A^2 is the transpose of A.at n=10A336614