Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #36 Apr 24 2016 12:03:35
%S 2,3,118,7,39,155,38,9,14,18659,13,8153,92,1317,106,35,26,49,34,57,68,
%T 253,327,1271,28,27,94,1633,46,161,415,1141,44,909589,86,161015,119,
%U 1293,82,673279,129,577679,4578,77,164,65,74,3589,76,147,115
%N a(n) = least k such that the remainder when 11^k is divided by k is n.
%H Daniel Morel, <a href="/A127819/b127819.txt">Table of n, a(n) for n = 1..189</a>
%H Daniel Morel, Robert G. Wilson v et al., <a href="/A127819/a127819_1.txt">Table of n, a(n) for n = 1..10000 with -1 for large entries where a(n) has not yet been found</a>
%t t = Table[0, {10000} ]; k = 1; While[ k < 4300000000, a = PowerMod[11, k, k]; If[a < 10001 && t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++ ]; t
%t f[n_]:=Module[{k=1},While[PowerMod[11,k,k]!=n,k++];k]; Array[f,51] (* _Harvey P. Dale_, Mar 12 2013 *)
%Y Cf. A036236, A078457, A119678, A119679, A127816, A119715, A119714, A127817, A127818, A127820, A127821.
%K nonn
%O 1,1
%A _Alexander Adamchuk_, Jan 30 2007
%E a(52) from _Max Alekseyev_ & Joe K. Crump (joecr(AT)carolina.rr.com), Feb 06 2007
%E a(108), a(514), a(754), a(808), a(820), a(880), a(934), a(948) added by _Daniel Morel_, May 18 2010, Jun 17 2010
%E a-file updated by _Max Alekseyev_, Dec 10 2010
%E a(112), a(348), a(810) added by _Daniel Morel_, Mar 12 2015