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 A129417 #32 Jun 02 2025 16:30:36
%S A129417 1,0,1,1,3,6,19,50,204,832,4330,25227,171886,1303725,10959478,
%T A129417 100230117,989280132,10455393155,117701173970,1405165683359,
%U A129417 17726785643045,235585551038117,3289367315407521,48136794098893837,736721822918719557,11768987500655142988
%N A129417 Number of isomorphism classes of connected 4-regular loopless multigraphs of order n.
%C A129417 Initial terms computed using software at http://users.cecs.anu.edu.au/~bdm/nauty/
%C A129417 Obtained from A129418 by an inverse Euler transform. - _R. J. Mathar_, Mar 09 2019
%H A129417 Brendan McKay and Adolfo Piperno, <a href="http://pallini.di.uniroma1.it">Nauty and Traces</a>
%o A129417 (nauty) geng -c -d1 ${n} -q | multig -r4 -u # _Natan Arie Consigli_, Jun 05 2017
%Y A129417 Column k=4 of A328682.
%Y A129417 Cf. A129418, A085549, A000421, A129419, A129421, A129423, A129425, A328682.
%K A129417 nonn
%O A129417 0,5
%A A129417 _Brendan McKay_, Apr 15 2007
%E A129417 a(0)-a(1) prepended by _Natan Arie Consigli_, Jun 05 2017
%E A129417 a(18)-a(25) from _Andrew Howroyd_, Mar 17 2020