A072119 Least k such that k(k+1)(k+2)...(k+n) divides C(2k,k).

1, 15, 42, 153, 153, 209, 943, 1989, 3318, 11725, 14322, 30191, 96113, 96113, 131054, 458671, 1040366, 1540061

Offset

1,2

Links

Table of n, a(n) for n=1..18.

Mathematica

g[n_] := Block[{k = 1}, While[ !IntegerQ[ Binomial[2k, k] / Product[i, {i, k, k + n}]], k++ ]; Return[k]]; Table[ a[n], {n, 1, 13}]

Prog

(PARI) for(n=1, 8, s=1; while(binomial(2*s, s)%prod(i=0, n, (s+i))>0, s++); print1(s, ", "))

Crossrefs

Sequence in context: A008976 A280232 A233302 * A069127 A137183 A173873

Adjacent sequences: A072116 A072117 A072118 * A072120 A072121 A072122

Keyword

nonn

Author

Benoit Cloitre, Jun 19 2002

Extensions

More terms from Naohiro Nomoto and Robert G. Wilson v, Jun 21 2002

a(14)-a(18) from Chai Wah Wu, Mar 27 2016

Status

approved