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 A066397 #12 Oct 12 2023 07:45:54 %S A066397 1,-2,6,-20,50,168,-4732,54024,-356670,-1558040,106069172,-2197188864, %T A066397 26605890220,22266781600,-12120090377400,402165029201744, %U A066397 -7732409047854318,38209542402620232,4126723132306766900,-211906442415502467360,5955735723962955009156 %N A066397 Reversion of 1 / sqrt(1 - 4*x) (the o.g.f. for the central binomial coefficients A000984) as if it were an e.g.f. %H A066397 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %H A066397 <a href="/index/Res#revert">Index entries for reversions of series</a> %p A066397 read transforms; t1 := 1 / sqrt(1 - 4*x); t2 := series(t1,x,50); t2 := seriestolist(%); REVEGF(%); # corrected by _Sean A. Irvine_, Oct 12 2023 %Y A066397 Cf. A000984. %K A066397 sign %O A066397 0,2 %A A066397 _N. J. A. Sloane_, Dec 24 2001 %E A066397 Name corrected by _Sean A. Irvine_, Oct 12 2023