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 A156618 #4 Jul 22 2025 06:21:02 %S A156618 7,-742,11978,-3740526,1099482930,-2202719155,6600663644,-26413901692, %T A156618 96840976853,-496325469560,2346251883960,-44006595799206, %U A156618 1345586183756654,-4127747481719463,10251870941174304 %N A156618 Denominators of Egyptian fraction for Pi-3 whose partial sums are the convergents. %C A156618 Numerators are all 1. %e A156618 3+1/a(0)=22/7 %e A156618 3+1/a(0)+1/a(1)=333/106 %e A156618 3+1/a(0)+1/a(1)+1/a(2)=355/113 %o A156618 (PARI) c0=3; for (k=2,30,m=contfracpnqn(contfrac(Pi,k));c1=m[1,1]/m[2,1];print1(1/(c1-c0),", ");c0=c1;) %Y A156618 Cf. A001466, A014013, A156019, A156020, A002485, A002486. %K A156618 sign %O A156618 0,1 %A A156618 _Jaume Oliver Lafont_, Feb 11 2009