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 A227725 #15 Nov 02 2021 13:16:14 %S A227725 2,2,1,2,3,2,2,7,14,23,2,15,70,345,3904 %N A227725 T(n,k) = number of small equivalence classes of n-ary Boolean functions that contain 2^k functions. %C A227725 Left diagonal (k=0) has only 2s. Two functions (contradiction and tautology) are always alone in their respective sec, regardless of arity. %C A227725 Second diagonal (k=1) is 2^n-1 (A000225). These are the n-ary linear Boolean functions. Each sec contains a row of a binary Walsh matrix and its complement. %C A227725 Right diagonal (k=n) is A051502, the numbers of small equivalence classes of n-ary functions, that contain the highest possible number of 2^n functions. %H A227725 Tilman Piesk, <a href="http://en.wikiversity.org/wiki/Equivalence_classes_of_Boolean_functions#sec">Small equivalence classes of Boolean functions</a> %H A227725 <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a> %e A227725 Triangle begins: Row sums (A000231) %e A227725 2 2 %e A227725 2 1 3 %e A227725 2 3 2 7 %e A227725 2 7 14 23 46 %e A227725 2 15 70 345 3904 4336 %Y A227725 Cf. A000231, A051502, A000225, A227722. %K A227725 nonn,tabl,more %O A227725 0,1 %A A227725 _Tilman Piesk_, Jul 22 2013