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 A250473 #12 Apr 02 2017 17:25:30 %S A250473 3,4,8,13,27,35,56,66,92,138,153,209,252,271,316,395,472,503,592,657, %T A250473 686,791,865,978,1140,1228,1269,1355,1396,1495,1848,1946,2110,2158, %U A250473 2456,2513,2694,2879,3006,3203,3397,3472,3827,3903,4046,4120,4582,5060,5227,5308,5473,5742,5831,6268,6542,6815,7106,7196,7487,7685,7783,8294,9028,9247,9353,9567,10350 %N A250473 Length of the maximal prefix of noncomposite numbers on row n of A249821. %C A250473 a(n) = Length of the initial fixed portion of the permutation at row n of A251721 & A251722. %C A250473 Also, for n > 1, the length of the maximal increasing prefix on row n of A249821. %F A250473 a(n) = A054272(n) + 1. %F A250473 a(n) = A250474(n) - 1. %F A250473 a(n) = 2 + A000879(n) - n. %o A250473 (define (A250473 n) (- (A250474 n) 1)) %Y A250473 One more than A054272. %Y A250473 One less than A250474. %Y A250473 Cf. A000879, A249821, A251721, A251722. %K A250473 nonn %O A250473 1,1 %A A250473 _Antti Karttunen_, Nov 23 2014