2860662domain: NAppears in sequencesGabcke sequence: a(0)=1; (n+1) a(n+1) = Sum_{k=0..n} 2^(4k+1) |E(2k+2)| a(n-k), where |E(2k+2)| are Euler numbers (E(2k)=(-1)^k A000364(k)).at n=4A087617