260497domain: NAppears in sequencesFibonacci sequence beginning 1, 5.at n=24A022095Main diagonal of array in A038150.at n=10A047923a(n) = 3*a(n-1) - a(n-2), a(0)=1, a(1)=6.at n=12A054492The lesser of two semiprime brothers.at n=16A289548