a(n) = A012249(2*n) / 2^(2*n-1).A012250a(n) = A012249(2*n) / 2^(2*n-1).Terms a(0) =1a(1) =3a(2) =40a(3) =1225a(4) =67956a(5) =5986134a(6) =769550496a(7) =136151219061External referencesoeis: A012250