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 A227723 #22 Dec 16 2017 22:43:55 %S A227723 0,1,3,6,7,15,22,23,24,25,27,30,31,60,61,63,105,107,111,126,127,255, %T A227723 278,279,280,281,282,283,286,287,300,301,303,316,317,318,319,360,361, %U A227723 362,363,366,367,382,383,384,385,386,387,390,391,393,395 %N A227723 Smallest Boolean functions from big equivalence classes (counted by A000616). %C A227723 Two Boolean functions belong to the same big equivalence class (bec) when they can be expressed by each other by negating and permuting arguments. E.g., when f(~p,r,q) = g(p,q,r), then f and g belong to the same bec. Geometrically this means that the functions correspond to hypercubes with binarily colored vertices that are equivalent up to rotation and reflection. %C A227723 Boolean functions correspond to integers, so each bec can be denoted by the smallest integer corresponding to one of its functions. There are A000616(n) big equivalence classes of n-ary Boolean functions. Ordered by size they form the finite sequence A_n. It is the beginning of A_(n+1), which leads to this infinite sequence A. %H A227723 Tilman Piesk, <a href="/A227723/b227723.txt">Table of n, a(n) for n = 0..9999</a> %H A227723 Tilman Piesk, <a href="http://en.wikiversity.org/wiki/Equivalence_classes_of_Boolean_functions#bec">Big equivalence classes of Boolean functions</a> %H A227723 Tilman Piesk, <a href="http://commons.wikimedia.org/wiki/File:0111_1000_1000_1000_Boolean_function_16*24.svg#File">bec of 4-ary functions</a> corresponding to a(85) = 854 = 0x0356 %H A227723 Tilman Piesk, <a href="http://pastebin.com/kdZBTYnU">MATLAB code used for the calculation</a> %H A227723 <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a> %F A227723 a( A000616 - 1 ) = a(2,5,21,401,...) = 3,15,255,65535,... = A051179 %e A227723 The 16 2-ary functions ordered in A000616(2) = 6 big equivalence classes: %e A227723 a a(n) Boolean functions hypercube (square) %e A227723 0 0 0000 empty %e A227723 1 1 0001, 0010, 0100, 1000 one in a corner %e A227723 2 3 0011, 1100, 0101, 1010 ones on a side %e A227723 3 6 0110, 1001 ones on a diagonal %e A227723 4 7 0111, 1011, 1101, 1110 ones in 3 corners %e A227723 5 15 1111 full %Y A227723 Cf. A227722 (does the same for small equivalence classes). %Y A227723 Cf. A000616, A051179. %K A227723 nonn %O A227723 0,3 %A A227723 _Tilman Piesk_, Jul 22 2013