64899domain: NAppears in sequencesa(n) = (4*n^3 - 6*n^2 + 8*n + 3)/3.at n=37A161712Integers n not of form 3m+1 such that for any integer k>0, n*10^k-1 has a divisor in the set { 7, 11, 13, 37 }.at n=15A243974