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 A119715 #23 Jan 30 2023 15:01:07 %S A119715 2,5,46,339,22,387497,11,535,10,111,38,8399,15,497,34,327,365,515,30, %T A119715 7219931,28,321,26,223793,44,10718597,242,35,2330,209,39,305,136,309, %U A119715 4382,10596486211,45,24751,7327,121,236,78821,55,4117,76,1751,30514339,83795,50,1333 %N A119715 a(n) = least k such that the remainder when 7^k is divided by k is n. %H A119715 Robert G. Wilson v, <a href="/A119715/a119715.txt">Table of n, a(n) for n = 1..10000 with -1 for those entries where a(n) has not yet been found</a> %t A119715 t = Table[0, {10000}]; k = 1; lst = {}; While[k < 4100000000, a = PowerMod[7, k, k]; If[ a<10001 && t[[a]]==0, t[[a]]=k; Print[{a,k}]]; k++ ]; t (* changed (to reflect the new limits) by _Robert G. Wilson v_, Jul 17 2009 *) %t A119715 lk[n_]:=Module[{k=1},While[PowerMod[7,k,k]!=n,k++];k]; Array[lk,50] (* The program will take a long time to run. *) (* _Harvey P. Dale_, Jan 29 2023 *) %Y A119715 Cf. A036236, A078457, A119678, A119679, A127816, A119714, A127817, A127818, A127819, A127820, A127821. %K A119715 nonn %O A119715 1,1 %A A119715 _Ryan Propper_, Jun 12 2006 %E A119715 a(36) = 10596486211 and later terms from _Ryan Propper_, Feb 02 2007