39545domain: NAppears in sequencesa(n) = Sum_{k=0..floor((n-5)/2)} T(n,k) * T(n,k+1), with T given by A008315.at n=6A027304Numbers k such that 127*2^k - 1 is prime.at n=2A050589a(n) = 26*n^2 - 1.at n=38A158551Second elementary symmetric function of the first n terms of (2,2,3,3,4,4,5,5...).at n=29A203299