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A072120 Least k such that n! divides C(2k,k). 0
1, 1, 2, 7, 14, 15, 43, 191, 239, 383, 383, 1919, 1919, 3967, 4091, 65471, 65471, 129023, 129023, 516095, 516095, 917503, 1046527, 8323071, 8323071, 16760831, 16760831, 113246207, 113246207, 367001599, 367001599, 4294967291 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

MATHEMATICA

a[n_] := Block[{k = 1}, While[ !IntegerQ[ Binomial[2k, k] / n! ], k++ ]; k]; Table[ a[n], {n, 1, 16}]

PROG

(PARI) for(n=1, 16, s=1; while(binomial(2*s, s)%n!>0, s++); print1(s, ", "))

CROSSREFS

Sequence in context: A102154 A102153 A032537 * A057126 A018349 A018363

Adjacent sequences:  A072117 A072118 A072119 * A072121 A072122 A072123

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 19 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 21 2002

More terms from Naohiro Nomoto (n_nomoto(AT)yabumi.com), Jun 26 2002

More terms from Don Reble (djr(AT)nk.ca), Jul 01 2002

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.