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 A034191 #33 Jul 22 2022 16:43:25
%S A034191 1,1,6,16,103,497,3253,19735,120843,681474,3561696,16938566,73500514,
%T A034191 290751447,1052201890,3492397119,10666911842,30064448972,78409442414,
%U A034191 189678764492,426539774378,893346071377,1745593733454
%N A034191 Number of binary codes of length 6 with n words.
%C A034191 Also number of 2-colorings of the vertices of the 6-cube having n nodes of one color.
%C A034191 The b-file shows the full sequence.
%D A034191 W. Y. C. Chen, Induced cycle structures of the hyperoctahedral group. SIAM J. Disc. Math. 6 (1993), 353-362.
%D A034191 H. Fripertinger, Enumeration, construction and random generation of block codes, Designs, Codes, Crypt., 14 (1998), 213-219.
%D A034191 R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1979.
%H A034191 R. W. Robinson, <a href="/A034191/b034191.txt">Table of n, a(n) for n = 0..64</a>
%H A034191 H. Fripertinger, <a href="http://www.mathe2.uni-bayreuth.de/frib/codes/tables.html">Isometry Classes of Codes</a>
%t A034191 (* From _Robert A. Russell_, May 08 2007: (Start) *)
%t A034191 P[ n_Integer ]:=P[ n ]=P[ n,n ];P[ n_Integer,_ ]:={}/;(n<0);(* partitions *)
%t A034191 P[ 0,_ ]:={{}};P[ n_Integer,1 ]:={Table[ 1,{n} ]};P[ _,0 ]:={};(*S.S. Skiena*)
%t A034191 P[ n_Integer,m_Integer ]:=Join[ Map[ (Prepend[ #,m ])&,P[ n-m,m ] ],P[ n,m-1 ] ];
%t A034191 AC[ d_Integer ]:=Module[ {C,M,p}, (* from W.Y.C. Chen algorithm *)
%t A034191 M[ p_List ]:=Plus@@p!/(Times@@p Times@@(Length/@Split[ p ]!));
%t A034191 C[ p_List,q_List ]:=Module[ {r,m,k,x},r=If[ 0==Length[ q ],1,2 2^
%t A034191 IntegerExponent[ LCM@@q,2 ] ];m=LCM@@Join[ p/GCD[ r,p ],q/GCD[ r,q ] ];
%t A034191 CoefficientList[ Expand[ Product[ (1+x^(k r))^((Plus@@Map[ MoebiusMu[ k/# ]
%t A034191 2^Plus@@GCD[# r,Join[ p,q ] ]&,Divisors[ k ] ])/(k r)),{k,1,m} ] ],x ] ];
%t A034191 Sum[ Binomial[ d,p ]Plus@@Plus@@Outer[ M[ #1 ]M[ #2 ]C[ #1,#2 ]2^(d-Length[ #1 ]-Length[ #2 ])&,P[ p ],P[ d-p ],1 ],{p,0,d} ]/(d!2^d) ];AC[ 6 ]
%t A034191 (* End *)
%Y A034191 Row n=6 of A039754.
%Y A034191 Cf. A034188, A034189, A034190, A034192, A034193, A034194, A034195, A034196, A034197.
%K A034191 nonn,fini,full
%O A034191 0,3
%A A034191 _N. J. A. Sloane_
%E A034191 Edited by _N. J. A. Sloane_ at the suggestion of _Andrew S. Plewe_, May 11 2007