Number of binary [ n,6 ] codes without 0 columns.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =1a(6) =6a(7) =25a(8) =99a(9) =385a(10) =1472a(11) =5676a(12) =22101a(13) =87404a(14) =350097a(15) =1413251a(16) =5708158a(17) =22903161a(18) =90699398a(19) =352749035a(20) =1342638839a(21) =4990325414a(22) =18090636016a(23) =63933709870a(24) =220277491298a(25) =740170023052