cp's OEIS Frontend

A224503 Smallest nontrivial prime power congruent to 1 mod n.

%I A224503 #19 Dec 23 2024 14:53:43
%S A224503 3,4,5,11,7,8,9,19,11,23,13,27,29,16,17,103,19,191,41,43,23,47,25,101,
%T A224503 27,109,29,59,31,32,97,67,103,71,37,149,191,79,41,83,43,173,89,181,47,
%U A224503 283,49,197,101,103,53,107,109,331,113,229,59
%N A224503 Smallest nontrivial prime power congruent to 1 mod n.
%H A224503 Alois P. Heinz, <a href="/A224503/b224503.txt">Table of n, a(n) for n = 2..10000</a>
%H A224503 David Harden, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2013-April/011015.html">Smallest groups with an irreducible representation of given dimension</a>
%p A224503 A224503 := proc(n)
%p A224503     local i;
%p A224503     for i from 2 do
%p A224503         if (A000961(i) mod n) = 1 then
%p A224503              return A000961(i);
%p A224503         end if;
%p A224503     end do:
%p A224503 end proc:
%p A224503 seq(A224503(n), n=2..100);
%t A224503 a[n_] := For[k = 2, True, k++, If[PrimePowerQ[k], If[Mod[k, n] == 1, Return[k]]]];
%t A224503 Table[a[n], {n, 2, 100}] (* _Jean-François Alcover_, May 18 2018 *)
%Y A224503 Cf. A000961, A024619, A080765.
%K A224503 nonn
%O A224503 2,1
%A A224503 _R. J. Mathar_, Apr 08 2013