This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A250002 #14 Nov 28 2014 22:24:26 %S A250002 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,2,1,0,0,0,0,2,8,8,2, %T A250002 0,0,0,0,4,21,36,21,4,0,0,0,0,7,47,114,114,47,7,0,0,0,0,11,93,306,453, %U A250002 306,93,11,0,0,0,0,16,168,730,1526,1526,730,168,16,0,0 %N A250002 Triangle read by rows: T(n,k) = number of inequivalent binary linear [n,k] codes minus C(n,k). %C A250002 The triangle of inequivalent binary linear [n,k] codes (A076831) looks much like Pascal's triangle (A007318). They start to differ in the middle of row 6. This triangle is the difference between them. Its row sums are A250003 - the difference between the numbers of inequivalent binary linear codes of length n (A076766) and the powers of two (A000079). %F A250002 a(n,k) = A076831(n,k) - A007318(n,k). %e A250002 k 0 1 2 3 4 5 6 7 8 9 10 11 sums %e A250002 n %e A250002 0 0 0 %e A250002 1 0 0 0 %e A250002 2 0 0 0 0 %e A250002 3 0 0 0 0 0 %e A250002 4 0 0 0 0 0 0 %e A250002 5 0 0 0 0 0 0 0 %e A250002 6 0 0 1 2 1 0 0 4 %e A250002 7 0 0 2 8 8 2 0 0 20 %e A250002 8 0 0 4 21 36 21 4 0 0 86 %e A250002 9 0 0 7 47 114 114 47 7 0 0 336 %e A250002 10 0 0 11 93 306 453 306 93 11 0 0 1273 %e A250002 11 0 0 16 168 730 1526 1526 730 168 16 0 0 4880 %e A250002 Row 6 of A076831 is (1,6,16,22,16,6,1) and row 6 of A007318 is (1,6,15,20,15,6,1). Row 6 of this triangle is their difference (0,0,1,2,1,0,0). %Y A250002 Cf. A076831, A007318, A250003. %K A250002 nonn,tabl %O A250002 0,25 %A A250002 _Tilman Piesk_, Nov 10 2014