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 A125648 #12 Apr 01 2025 18:13:13
%S A125648 257,4373,735443,3294173,28723679,533810141,38277341,47579927,
%T A125648 982740799,33956348611,77141582851,174329354539,82984891817,
%U A125648 109051450427,83209719751,1352085061013,171168499897,1822904926391,2870322429133,3589197993463,2603594622571,5834621843669,1411025860033,20635686238253,1580041060459,26763849212297,8216934406781,28482190726739,97876187600351
%N A125648 Smallest odd prime base q such that p^7 divides q^(p-1) - 1, where p = Prime[n].
%H A125648 W. Keller and J. Richstein <a href="http://www1.uni-hamburg.de/RRZ/W.Keller/FermatQuotient.html">Fermat quotients that are divisible by p</a>.
%o A125648 (PARI) { a125648(n) = my(p, x, r); if(n==1, return(257)); p=prime(n); x=znprimroot(p^7)^(p^6); vecmin( vector(p-1, i, forprimestep(y=2,oo,x^i,r=y;break); r) ); } \\ _Max Alekseyev_, May 30 2007; updated Apr 01 2025
%Y A125648 Cf. A125609, A125610, A125611, A125612, A125632, A125633, A125634, A125635, A125636, A125637, A125645, A125646, A125647, A125649.
%K A125648 nonn
%O A125648 1,1
%A A125648 _Alexander Adamchuk_, Nov 29 2006
%E A125648 More terms from _Max Alekseyev_, May 30 2007