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a(n) = least k such that the remainder when 14^k is divided by k is n.
34

%I #8 Oct 02 2013 15:12:55

%S 13,3,11,5,33,10,1967,9,23587,18,2733,46,17651,15,93929,20,303,178,

%T 145,22,12901,58,2721,25,17990951,27,143,36,85,166,646123,82,

%U 2439143677,55,63,76,319,123,295,52,51,77,247380287953,45,5779134947,90,87,74,175,146

%N a(n) = least k such that the remainder when 14^k is divided by k is n.

%H Robert G. Wilson v, <a href="/A128154/a128154.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 < 3000000000, a = PowerMod[14, k, k]; If[a < 10001 && t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++ ]; t

%t lk[n_]:=Module[{k=1},While[PowerMod[14,k,k]!=n,k++];k]; Array[lk,20] (* _Harvey P. Dale_, Aug 17 2013 *)

%Y Cf. A036236, A078457, A119678, A119679, A127816, A119715, A119714, A127817, A127818, A127819, A127820, A127821, A128155, A128156, A128157, A128158, A128159, A128160, A128149, A128150.

%K hard,nonn

%O 1,1

%A _Alexander Adamchuk_, Feb 16 2007

%E More terms from _Ryan Propper_, Feb 28 2007

%E a(43) from _Hagen von Eitzen_, Aug 16 2009