Binomial transform of A081250.

Terms

a(0) =1a(1) =4a(2) =18a(3) =76a(4) =312a(5) =1264a(6) =5088a(7) =20416a(8) =81792a(9) =327424a(10) =1310208a(11) =5241856a(12) =20969472a(13) =83881984a(14) =335536128a(15) =1342160896a(16) =5368676352a(17) =21474770944a(18) =85899214848a(19) =343597121536