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 A054930 #13 Jan 16 2022 22:09:26 %S A054930 1,1,2,3,4,10,8,23,27,70,56,312,180,700,1096,2131,2068,11020,7316, %T A054930 34008,44232,104968,95420,531296,419654,1398500,1864674,5638352, %U A054930 4794088,33597760,17896832 %N A054930 Number of complementary pairs of circulant digraphs on n nodes. %H A054930 V. A. Liskovets, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL3/LISK/Derseq.html">Some easily derivable sequences</a>, J. Integer Sequences, 3 (2000), #00.2.2. %F A054930 Average of A049297 and A049309. %F A054930 a(2*n) = A049297(2*n)/2; a(2*n-1) = (A049297(2*n-1) + A049309(n))/2. - _Andrew Howroyd_, Jan 16 2022 %Y A054930 Cf. A049297, A049309, A054929. %K A054930 nonn,more %O A054930 1,3 %A A054930 _N. J. A. Sloane_, May 24 2000 %E A054930 a(12)-a(31) added by _Andrew Howroyd_, Jan 16 2022