Binomial transform of b(n) = (0, 0, A007910).

Terms

a(0) =0a(1) =0a(2) =1a(3) =5a(4) =17a(5) =51a(6) =149a(7) =439a(8) =1309a(9) =3927a(10) =11797a(11) =35423a(12) =106301a(13) =318903a(14) =956645a(15) =2869807a(16) =8609293a(17) =25827879a(18) =77483893a(19) =232452191a(20) =697357085a(21) =2092071255a(22) =6276212741a(23) =18828636175a(24) =56485906477a(25) =169457719431a(26) =508373162389