Number of binary [ n,3 ] codes without 0 columns.

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =6a(5) =12a(6) =21a(7) =34a(8) =54a(9) =82a(10) =120a(11) =174a(12) =244a(13) =337a(14) =458a(15) =613a(16) =808a(17) =1056a(18) =1361a(19) =1738a(20) =2200a(21) =2759a(22) =3431a(23) =4240a(24) =5198a(25) =6333a(26) =7670a(27) =9235a(28) =11056a(29) =13175