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 A068503 #13 May 14 2022 11:30:35 %S A068503 1,1,1,3,1,3,1,9,1,1,3,9,1,3,1,1,1,3,3,1,9,3,1,1,3,1,3,1,27,1,9,1,1,3, %T A068503 1,3,3,81,1,1,1,9,1,3,1,9,3,3,1,3,1,1,3,1,1,1,1,27,3,1,3,1,9,1,3,1,3, %U A068503 3,1,3,1,1,3,3,27,1,1,9,1,3,1,3,1,27,3,1,1,3,1,3,1,1,243,1,3,1,1,1,9,27 %N A068503 Highest power of 3 dividing prime(n)-1. %H A068503 Amiram Eldar, <a href="/A068503/b068503.txt">Table of n, a(n) for n = 1..10000</a> %F A068503 a(n) = A038500(A006093(n)). - _Michel Marcus_, Nov 24 2013 %F A068503 a(n) = 3^A099584(n). - _Michel Marcus_, Nov 24 2013 %t A068503 a[n_] := 3^IntegerExponent[Prime[n] - 1, 3]; Array[a, 100] (* _Amiram Eldar_, May 14 2022 *) %o A068503 (PARI) a(n) = 3^valuation(prime(n)-1, 3); \\ _Michel Marcus_, Nov 24 2013 %Y A068503 Cf. A006093, A038500, A099584. %K A068503 easy,nonn %O A068503 1,4 %A A068503 _Benoit Cloitre_, Mar 11 2002