Number of 4 X n binary matrices without unit columns up to row and column permutations.

Terms

a(0) =1a(1) =4a(2) =14a(3) =44a(4) =127a(5) =335a(6) =830a(7) =1931a(8) =4258a(9) =8943a(10) =17984a(11) =34765a(12) =64873a(13) =117220a(14) =205718a(15) =351552a(16) =586348a(17) =956393a(18) =1528350a(19) =2396631a(20) =3693123a(21) =5599550a(22) =8363304a(23) =12317274a(24) =17904795a(25) =25710327a(26) =36497466a(27) =51255153a(28) =71253960a(29) =98113791