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 A063030 #22 Jul 09 2025 03:56:20
%S A063030 0,1,1,2,6,19,63,220,795,2942,11099,42536,165126,647955,2565946,
%T A063030 10241616,41158598,166402323,676338003,2761988994,11327162406,
%U A063030 46631572295,192638451780,798316442580,3317866307145,13825837134096
%N A063030 Reversion of y - y^2 - y^4 + y^5.
%H A063030 R. J. Mathar, <a href="/A063030/b063030.txt">Table of n, a(n) for n = 0..105</a>
%H A063030 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A063030 D-finite with recurrence 1458*n*(n-1)*(n-2)*(2*n-1) *(981649511*n -2631216939)*a(n) -486*(n-1)*(n-2) *(24210415932*n^3 -114067288649*n^2 +155533650884*n -64732315335)*a(n-1) +54*(n-2) *(39787015892*n^4 -313539301751*n^3 +992577496688*n^2 -1613867842189*n +1173502139880)*a(n-2) +(-27607572942679*n^5 +295135536608825*n^4 -1205223186688595*n^3 +2314131935158975*n^2 -2033367943220766*n +619177732684560)*a(n-3) -5*(5*n-21) *(5408009*n +1144402484)*(5*n-19) *(5*n-18)*(5*n-17) *a(n-4)=0. - _R. J. Mathar_, Mar 21 2022
%F A063030 a(n+1) = (1/(n+1)) * Sum_{k=0..floor(n/3)} binomial(n+k,n) * binomial(2*n-3*k,n). - _Seiichi Manyama_, Sep 26 2023
%t A063030 CoefficientList[InverseSeries[Series[y - y^2 - y^4 + y^5, {y, 0, 30}], x], x]
%o A063030 (PARI) a(n)=if(n<1,0,polcoeff(serreverse(x-x^2-x^4+x^5+x*O(x^n)),n))
%Y A063030 Cf. A006013, A063020.
%Y A063030 Cf. A063026.
%K A063030 nonn,easy
%O A063030 0,4
%A A063030 _Olivier Gérard_, Jul 05 2001