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 A356309 #16 Nov 07 2022 02:12:23
%S A356309 0,1,2,6,4,5,6,7,8,12,30,11,12,13,14,30,16,17,18,19,30,24,22,23,24,30,
%T A356309 26,30,28,29,30,31,32,36,34,210,36,37,38,42,60,41,210,43,44,60,46,47,
%U A356309 48,210,60,54,52,53,54,60,210,60,58,59,60,61,62,210,64,65,66,67,68,72,210,71,72,73,74,90,76,2310,78
%N A356309 The least j >= n such that n and A276086(j) are relatively prime, where A276086 is the primorial base exp-function.
%H A356309 Antti Karttunen, <a href="/A356309/b356309.txt">Table of n, a(n) for n = 0..11550</a>
%H A356309 Antti Karttunen, <a href="/A356309/a356309.txt">Data supplement: n, a(n) computed for n = 0..65537</a>
%H A356309 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F A356309 a(n) = n + A356302(n).
%t A356309 f[nn_] := Block[{m = 1, i = 1, n = nn, p}, While[n > 0, p = Prime[i]; m *= p^Mod[n, p]; n = Quotient[n, p]; i++]; m]; Array[Block[{k = #}, While[! CoprimeQ[#, f[k]], k++]; k] &, 79, 0] (* _Michael De Vlieger_, Nov 06 2022, after _Jean-François Alcover_ at A276086 *)
%o A356309 (PARI) A356309(n) = (n+A356302(n)); \\ See code in the latter sequence.
%Y A356309 Cf. A276086, A356302, A356313.
%Y A356309 Cf. A324583 (positions of the fixed points), A356314 (positions of the terms that are primorial numbers), A356316 (where a(n) is a multiple of n), A356318 (where a nontrivial multiple), A356319 (where n < a(n) < 2*n).
%K A356309 nonn
%O A356309 0,3
%A A356309 _Antti Karttunen_, Nov 04 2022