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 A113636 #23 Jun 21 2025 20:24:05
%S A113636 2,2,3,5,5,7,7,9,10,11,11,13,13,15,16,17,17,19,19,21,22,23,23,25,26,
%T A113636 27,28,29,29,31,31,33,34,35,36,37,37,39,40,41,41,43,43,45,46,47,47,49,
%U A113636 50,51,52,53,53,55,56,57,58,59,59,61,61,63,64,65,66,67,67,69,70,71,71,73
%N A113636 In the sequence of positive integers add 1 to each nonprime number.
%C A113636 This is the complement of sequence A014683.
%C A113636 Möbius transform of A380449(n). - _Wesley Ivan Hurt_, Jun 21 2025
%F A113636 a(n) = A014684(n) + 1. - _Bill McEachen_, Nov 01 2020
%F A113636 From _Wesley Ivan Hurt_, Jun 21 2025: (Start)
%F A113636 a(n) = n + c(n), where c = A005171.
%F A113636 a(n) = Sum_{d|n} A380449(d) * mu(n/d). (End)
%t A113636 Array[# + Boole[! PrimeQ@ #] &, 72] (* _Michael De Vlieger_, Nov 05 2020 *)
%o A113636 (PARI) a(n) = if (!isprime(n), n+1, n); \\ _Michel Marcus_, Nov 06 2020
%Y A113636 Cf. A005171, A014683, A014684, A113523, A113638, A179278, A380449.
%K A113636 easy,nonn
%O A113636 1,1
%A A113636 _Cino Hilliard_, Jan 15 2006
%E A113636 Offset 1 from _Michel Marcus_, Nov 06 2020