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 A249340 #10 Oct 26 2014 20:50:23 %S A249340 1,3,5,13,20,39,50,70,80,97,131,142,193,240,257,296,322,379,397,435, %T A249340 478,490,542,569,629,736,758,764,828,835,872,1067,1100,1209,1214,1369, %U A249340 1414,1468,1514,1549,1606,1681,1700,1853,1871,1903,1931,2116,2244,2293,2303,2343 %N A249340 Position of the first occurrence of n-th noncomposite number, A008578(n), in A249336; positions of records in A249338. %F A249340 a(n) = A249339(n+1) - 1. %F A249340 Other identities. For all n >= 1: %F A249340 A249336(a(n)) = A008578(n). %F A249340 A249338(a(n)) = n-1. %o A249340 (Scheme, with _Antti Karttunen_'s IntSeq-library, two alternative definitions) %o A249340 (define A249340 (MATCHING-POS 1 1 (lambda (n) (and (= 1 (A249336 (+ 1 n))) (or (= 1 (A249336 n)) (prime? (A249336 n))))))) %o A249340 (define A249340 (RECORD-POS 1 1 A249338)) %Y A249340 Cf. A249336, A249338, A249339. %K A249340 nonn %O A249340 1,2 %A A249340 _Antti Karttunen_, Oct 26 2014