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%I #7 Feb 28 2014 09:16:51
%S 1,1,2,1,1,1,3,1,2,1,1,1,3,1,2,1,1,1,2,1,1,1,1,1,3,1,2,1,1,1,1,1,2,1,
%T 1,1,3,1,2,1,1,1,2,1,1,1,1,1,2,1,1,1,1,1,3,1,2,1,1,1,1,1,2,1,1,1,3,1,
%U 2,1,1,1,1,1,2,1,1,1,2,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,3,1,2
%N Least positive integer j such that n divides C(k)-C(j) , where k, as in A205793, is the least number for which there is such a j, and C=A002808 (composite numbers).
%C Is this sequence bounded? For a guide to related sequences, see A204892.
%e 1 divides C(2)-C(1) -> k=2, j=1
%e 2 divides C(2)-C(1) -> k=2, j=1
%e 3 divides C(4)-C(2) -> k=4, j=2
%e 4 divides C(3)-C(1) -> k=3, j=1
%e 5 divides C(4)-C(1) -> k=4, j=1
%e 6 divides C(5)-C(1) -> k=5, j=1
%t s = Select[Range[2, 120], ! PrimeQ[#] &]
%t lk = Table[
%t NestWhile[# + 1 &, 1,
%t Min[Table[Mod[s[[#]] - s[[j]], z], {j, 1, # - 1}]] =!= 0 &], {z, 1,
%t Length[s]}]
%t Table[NestWhile[# + 1 &, 1,
%t Mod[s[[lk[[j]]]] - s[[#]], j] =!= 0 &], {j, 1, Length[lk]}]
%t (* _Peter J. C. Moses_, Jan 27 2012 *)
%Y Cf. A204892.
%K nonn
%O 1,3
%A _Clark Kimberling_, Feb 01 2012
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