Number of binary [ n,3 ] codes.

Terms

a(0) =0a(1) =0a(2) =1a(3) =4a(4) =10a(5) =22a(6) =43a(7) =77a(8) =131a(9) =213a(10) =333a(11) =507a(12) =751a(13) =1088a(14) =1546a(15) =2159a(16) =2967a(17) =4023a(18) =5384a(19) =7122a(20) =9322a(21) =12081a(22) =15512a(23) =19752a(24) =24950a(25) =31283a(26) =38953a(27) =48188a(28) =59244a(29) =72419