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 A171876 #4 Nov 09 2018 15:42:11 %S A171876 1,1,1,1,1,3,3,1,1,4,6,19,27,50,56,1,1,5,10,47,131,472,1326,3779,9013, %T A171876 19963,38073,65664,98804,133576,158658,1,1,6,16,103,497,3253,19735, %U A171876 120843,681474,3561696 %N A171876 Mutual solutions to two classification counting problems: binary block codes of wordlength J with N used words; and classifications of N elements by J partitions. %C A171876 This connection was conjectured by _Robert Munafo_, then proved by _Andrew Weimholt_. %C A171876 A(n) counts 2-colorings of a J-dimensional hypercube with N red vertices and 2^J-N black, each edge has at most one red vertex. - _Andrew Weimholt_, Dec 30 2009 %C A171876 This sequence contains terms of A039754 that are found in A171871/A171872. They occur in blocks of length 2^(J-1) as shown here: %C A171876 1 %C A171876 1,1 %C A171876 1,1,3,3 %C A171876 1,1,4,6,19,27,50,56 %C A171876 1,1,5,10,47,131,472,1326,3779,9013,19963,38073,65664,98804,133576,158658 %H A171876 Harald Fripertinger, <a href="http://www.mathe2.uni-bayreuth.de/frib/html2/construction/blockcodes_2.html">Enumeration of block codes</a> %H A171876 R. Munafo, <a href="http://mrob.com/pub/math/seq-a005646.html">Classifications of N Elements</a> %Y A171876 Cf. A039754, A171872, A171871, A005646. %K A171876 nonn %O A171876 0,6 %A A171876 _Robert Munafo_, Jan 21 2010