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 A002500 M1868 N0740 #23 Jan 29 2022 01:05:38 %S A002500 1,2,8,44,436,7176,222368,12376880,1302871456,254079924896, %T A002500 94287450368768,65986000800656832,88430997899765949952, %U A002500 226039101814259861321856,1112311767839787173832758784 %N A002500 Number of self-converse relations on n points. %D A002500 F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 155, Table 6.6.1. %D A002500 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002500 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002500 Sean A. Irvine, <a href="/A002500/b002500.txt">Table of n, a(n) for n = 0..50</a> %H A002500 F. Harary and E. M. Palmer, <a href="http://dx.doi.org/10.1112/S0025579300003910">Enumeration of self-converse digraphs</a>, Mathematika, 13 (1966), 151-157. %F A002500 Equals A029849*2 - A000595. Cf. A002499. %K A002500 nonn,nice,easy %O A002500 0,2 %A A002500 _N. J. A. Sloane_ %E A002500 In the Encyclopedia of Integer Sequences the n=6 term is given incorrectly as 484256. %E A002500 Corrected and extended with formula by _Christian G. Bower_, Jun 15 1998