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 A054708 #13 Aug 25 2024 10:00:18
%S A054708 1,1,1,2,4,1,2,2,3,4,10,2,12,2,4,2,16,3,3,4,2,10,22,2,4,12,9,3,7,4,15,
%T A054708 4,10,16,5,6,9,3,12,4,40,2,6,10,12,22,23,2,3,4,16,12,26,9,20,3,3,7,29,
%U A054708 4,60,15,4,8,12,10,66,16,22,5,70,6,24,9,4,6,11,12,78,4,27,40,41,3,16,6
%N A054708 Number of powers of 7 modulo n.
%H A054708 Amiram Eldar, <a href="/A054708/b054708.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from David W. Wilson)
%F A054708 a(n) = A007738(n) + A214411(n). - _Amiram Eldar_, Aug 25 2024
%t A054708 a[n_] := Module[{e = IntegerExponent[n, 7]}, e + MultiplicativeOrder[7, n/7^e]]; Array[a, 100] (* _Amiram Eldar_, Aug 25 2024 *)
%Y A054708 Cf. A007738, A214411.
%Y A054708 Cf. A054703 (base 2), A054704 (3), A054705 (4), A054706 (5), A054707 (6), A054709 (8), A054717 (9), A054710 (10), A351524 (11), A054712 (12), A054713 (13), A054714 (14), A054715 (15), A054716 (16).
%K A054708 easy,nonn
%O A054708 1,4
%A A054708 _Henry Bottomley_, Apr 20 2000