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A123621 Greatest k <= n/2 such that n divides binomial(n,k). 1
0, 1, 1, 1, 2, 1, 3, 3, 4, 4, 5, 6, 6, 5, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 15, 15, 15, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 25, 26, 26, 27, 28, 28, 28, 29, 29, 30, 29, 31, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 37, 37 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

A007318(n,a(n)) mod n = 0;

a(p) = floor(p/2) for primes p.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..1000

Index entries for triangles and arrays related to Pascal's triangle

Eric Weisstein's World of Mathematics, Binomial Coefficient

MATHEMATICA

gk[n_]:=Module[{k=Floor[n/2]}, While[!Divisible[Binomial[n, k], n], k--]; k]; Array[gk, 80] (* Harvey P. Dale, Nov 22 2013 *)

CROSSREFS

Sequence in context: A173989 A093068 A097357 * A151662 A049786 A282611

Adjacent sequences:  A123618 A123619 A123620 * A123622 A123623 A123624

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 03 2006

STATUS

approved

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Last modified February 28 11:08 EST 2020. Contains 332323 sequences. (Running on oeis4.)