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 A320488 #18 Jan 28 2020 03:41:44 %S A320488 1,1,0,1,4,14,65,572,7434,163284,5736792,342169618,33534958026, %T A320488 5442700283638,1484664947481018,664513607618098252, %U A320488 508538464299684269212,635542752091150346032474,1374528064543284187245552390,4842758246111267151697826493193,29772724415959420224886585241636839 %N A320488 Inverse Euler transform of A004104. %C A320488 The inverse Euler transform of A004104 does not give the number of connected self-dual signed graphs. The combinatorial interpretation of this sequence is that of either a connected self-dual signed graph or a pair of distinct connected signed graphs which are dual to each other (but not self-dual). - _Andrew Howroyd_, Jan 26 2020 %H A320488 Andrew Howroyd, <a href="/A320488/b320488.txt">Table of n, a(n) for n = 0..50</a> %H A320488 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %Y A320488 Cf. A004102, A004104, A053465, A320499. %K A320488 nonn %O A320488 0,5 %A A320488 _N. J. A. Sloane_, Oct 25 2018 %E A320488 Definition edited by _Andrew Howroyd_, Jan 26 2020