632481024domain: NAppears in sequencesa(1) = 1, a(2) = 6, for n >= 3; a(n) = the smallest number greater than a(n-1) such that [[a(n-2) + a(n-1)] * [a(n-2) + a(n)] * [a(n-1) + a(n)]] / [a(n-2) * a(n-1) * a(n)] is an integer.at n=15A182752a(n) = phi(n^8) = n^7*phi(n).at n=13A306412