185257domain: NAppears in sequencesa(n) = a(n-1) + 5*a(n-2) for n >= 2, a(0)=1, a(1)=2.at n=12A133407Numbers that are both a sum of two positive cubes and a difference of two consecutive cubes.at n=11A225909a(n) = Sum_{j=1..n} Sum_{k=1..n} phi(j*k).at n=35A372633