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 A346489 #7 Feb 19 2023 14:00:33 %S A346489 1,2,3,4,10,19,24,46,109,430,669,3245,6057,7837,33067,77777,476643, %T A346489 601855,3556550,5216954,15739663,41146179,189961757,882206624, %U A346489 3325059246,15581005618,23007498153,37607875618 %N A346489 a(n) is the index of the smallest prime whose digits sum to n-th prime. %F A346489 a(n) = A000720(A054750(n)). %F A346489 a(n) = min {k : A007605(k) = prime(n)}. %e A346489 a(10) = 430 because prime(430) = 2999, 2 + 9 + 9 + 9 = 29 = prime(10) and this is the smallest such number. %t A346489 Module[{nn=522*10^4,tbl},tbl=Table[{n,Total[IntegerDigits[Prime[n]]]},{n,nn}];Table[SelectFirst[tbl,#[[2]]==Prime[n]&],{n,20}]][[;;,1]] (* The program generates the first 20 terms of the sequence. *) (* _Harvey P. Dale_, Feb 19 2023 *) %Y A346489 Cf. A000040, A000720, A007605, A028834, A046704, A046864, A054750, A075177. %K A346489 nonn,base %O A346489 1,2 %A A346489 _Ilya Gutkovskiy_, Jul 19 2021