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 A346599 #26 Jul 29 2021 12:49:48 %S A346599 1,3,4,5,15,7,8,9,45,11,33,13,91,35,16,17,51,19,76,84,77,23,69,25,65, %T A346599 27,63,29,87,31,32,88,187,85,180,37,703,247,104,41,123,43,172,99,115, %U A346599 47,141,49,175,255,204,53,159,135,280,133,551,59,177,61,1891,217,64,160,143,67 %N A346599 Smallest k such that A344005(k) = n. %H A346599 Chai Wah Wu, <a href="/A346599/b346599.txt">Table of n, a(n) for n = 1..20000</a> (terms 1..156 from N. J. A. Sloane, terms 157..420 from Michel Marcus). %e A346599 A344005(15) = 5 is the first appearance of 5 in A344005, so a(5) = 15. %t A346599 Array[(k=1;n=1;While[m=1;While[!Divisible[m(m+1),n],m++];m!=#,n++];n)&,70] (* _Giorgos Kalogeropoulos_, Jul 29 2021 *) %o A346599 (PARI) f(n) = my(m=1); while (m*(m+1) %n, m++); m; \\ A344005 %o A346599 a(n) = my(k=1); while (f(k) !=n, k++); k; \\ _Michel Marcus_, Jul 29 2021 %Y A346599 Cf. A344005, A346598. %K A346599 nonn %O A346599 1,2 %A A346599 _Robert Dougherty-Bliss_ and _N. J. A. Sloane_, Jul 28 2021