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A205551 The least j such that n divides k^k-j^j, where k (as in A205546) is the least number for which there is such a j. 2

%I #6 Dec 04 2016 19:46:26

%S 1,1,1,2,1,2,2,4,2,4,1,2,1,2,1,4,1,2,4,4,2,1,2,4,4,1,3,2,4,4,1,4,3,4,

%T 1,2,4,1,1,4,5,2,1,1,1,2,4,4,6,4,1,1,7,3,6,6,7,4,5,4,5,2,2,4,1,3,6,4,

%U 2,6,1,8,3,1,6,1,6,3,8,4,6,5,12,2,1,4,1,6,2,6,1,2,9,4,5,4,6,6,3

%N The least j such that n divides k^k-j^j, where k (as in A205546) is the least number for which there is such a j.

%C For a guide to related sequences, see A204892.

%e 1 divides 2^2-1^1 -> k=2, j=1

%e 2 divides 3^3-1^1 -> k=3, j=1

%e 3 divides 2^2-1^1 -> k=2, j=1

%e 4 divides 4^4-2^2 -> k=2, j=2

%t s = Table[n^n, {n, 1, 120}];

%t lk = Table[NestWhile[# + 1 &, 1,

%t Min[Table[Mod[s[[#]] - s[[j]], z], {j, 1, # - 1}]] =!= 0 &], {z, 1, Length[s]}]

%t Table[NestWhile[# + 1 &, 1,

%t Mod[s[[lk[[j]]]] - s[[#]], j] =!= 0 &],

%t {j, 1, Length[lk]}]

%t (* _Peter J. C. Moses_, Jan 27 2012 *)

%Y Cf. A204892.

%K nonn

%O 1,4

%A _Clark Kimberling_, Jan 31 2012

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)