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 A165724 #11 Jul 07 2023 11:14:41 %S A165724 7,13,19,55,103,121,127,163,253,391,721,793,1063,1441,2719,3313,9595, %T A165724 13045,17863,21889,46243,49891 %N A165724 Digit sums of A092571. %C A165724 Primes in this sequence are 7, 13, 19, 103, 127,163, .... %H A165724 Dario Alpern, <a href="https://www.alpertron.com.ar/ECM.HTM">Factorization using the Elliptic Curve Method</a> %F A165724 a(n) = 1 + 6*A056658(n). [_R. J. Mathar_, Sep 25 2009] %F A165724 a(n) = A007953(A092571(n)). - _Michel Marcus_, Jul 07 2023 %e A165724 The digit sum of 6666666666666666666666666666666666666666661 is 253. %Y A165724 Cf. A007953, A056658, A092571. %K A165724 base,nonn,more %O A165724 1,1 %A A165724 _Parthasarathy Nambi_, Sep 25 2009 %E A165724 More terms from _R. J. Mathar_, Sep 25 2009