103660domain: NAppears in sequencesa(n) = 2*L(n) + L(n-1) - n, L(n) = n-th Lucas number A000204(n).at n=21A133641Integers k equal to the sum over A024816(t) mod t, for some steps, starting with t = k and then using the result to feed the next calculation.at n=30A377002