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 A157193 #4 Jul 22 2025 06:22:33
%S A157193 1,4,44,1953,4179942,42836179578838,3958573977160882295479936105,
%T A157193 36328295343356352083453782833218820307659379901717630389
%N A157193 Greedy Egyptian fraction expansion for 4/Pi.
%C A157193 Sum_{n>=0}1/a(n)=4/Pi
%C A157193 Truncating the series to three terms yields the convergent 22/7 as an approximation to Pi:
%C A157193 1+1/4+1/44=14/11=4/(22/7)
%H A157193 Wikipedia, <a href="http://en.wikipedia.org/wiki/Greedy_algorithm_for_Egyptian_fractions">Greedy algorithm for Egyptian fractions</a>
%o A157193 (PARI) x=4/Pi; for (k=0,7,d=ceil(1/x);x=x-1/d;print(d,", "))
%Y A157193 Cf. A088538, A154956, A156618.
%K A157193 frac,nonn
%O A157193 0,2
%A A157193 _Jaume Oliver Lafont_, Feb 24 2009