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 A205786 Least positive integer j such that n divides C(k)-C(j), where k, as in A205785, is the least number for which there is such a j, and C=A205825. 1
 1, 1, 3, 4, 2, 2, 1, 4, 3, 2, 1, 4, 3, 7, 6, 2, 3, 2, 1, 5, 7, 4, 3, 6, 5, 2, 4, 8, 5, 6, 4, 8, 4, 8, 7, 4, 5, 5, 3, 6, 12, 7, 3, 6, 6, 6, 3, 8, 7, 5, 8, 2, 3, 4, 7, 8, 3, 5, 2, 6, 6, 4, 9, 8, 6, 4, 7, 8, 3, 7, 6, 9, 1, 5, 10, 9, 7, 6, 8, 8, 9, 12, 5, 8, 8, 9, 6, 6, 1, 6, 7, 6, 4, 11, 5, 8, 8 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS For a guide to related sequences, see A204892. LINKS EXAMPLE 1 divides C(2)-C(1) -> k=2, j=1; 2 divides C(3)-C(1) -> k=3, j=1; 3 divides C(4)-C(3) -> k=4, j=3; 4 divides C(5)-C(4) -> k=5, j=4; 5 divides C(4)-C(2) -> k=4, j=2. MATHEMATICA s = Table[n!/Ceiling[n/2]!, {n, 1, 120}]; lk = Table[   NestWhile[# + 1 &, 1,    Min[Table[Mod[s[[#]] - s[[j]], z], {j, 1, # - 1}]] =!= 0 &], {z, 1,     Length[s]}] Table[NestWhile[# + 1 &, 1,   Mod[s[[lk[[j]]]] - s[[#]], j] =!= 0 &], {j, 1, Length[lk]}] (* Peter J. C. Moses, Jan 27 2012 *) CROSSREFS Cf. A204892, A205825. Sequence in context: A096411 A228340 A227004 * A213812 A143486 A257820 Adjacent sequences:  A205783 A205784 A205785 * A205787 A205788 A205789 KEYWORD nonn AUTHOR Clark Kimberling, Feb 01 2012 STATUS approved

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Last modified January 17 18:37 EST 2019. Contains 319251 sequences. (Running on oeis4.)