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 A129227 #13 Apr 11 2021 04:18:57 %S A129227 3,3,3,11,5,17,7,5,7,31,17,37,37,43,47,5,53,53,59,31,13,23,71,73,13, %T A129227 79,83,29,13,47,97,97,103,53,109,113,29,17,61,31,127,131,67,137,47,71, %U A129227 73,149,151,157,157,163,83,167,43,173,179,181,37,47,191,97,197,67,17,103 %N A129227 a(n) is that prime number, p, less than n*Pi such that n*Pi/p has the smallest fractional part. %e A129227 a(4)=11 because 4*Pi/11 = 1.142... and the fractional part 0.142... represents the smallest remainder resulting from the division of 4*Pi by a prime number less than 4*Pi. %t A129227 f[n_] := (p = Denominator[ Min[ FractionalPart[(n*Pi / Prime@ Range@ PrimePi[n*Pi])]] [[2]]]; If[p == 1, n, p]); Array[f, 66] (* _Robert G. Wilson v_, Apr 08 2007 *) %o A129227 (Sage) A129227 = lambda n: sorted(primes(floor(n*pi)+1), key=lambda p: (n*pi/p-floor(n*pi/p)))[0] # _D. S. McNeil_, Dec 11 2010 %Y A129227 Cf. A129228. %K A129227 easy,nonn %O A129227 1,1 %A A129227 _Axel Harvey_, Apr 04 2007 %E A129227 Edited and extended by _Robert G. Wilson v_, Apr 08 2007