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%I #9 Oct 19 2017 03:14:04
%S 1,1,2,7,14,15,43,191,239,383,383,1919,1919,3967,4091,65471,65471,
%T 129023,129023,516095,516095,917503,1046527,8323071,8323071,16760831,
%U 16760831,113246207,113246207,367001599,367001599,4294967291
%N Least k such that n! divides C(2k,k).
%t a[n_] := Block[{k = 1}, While[ !IntegerQ[ Binomial[2k, k] / n! ], k++ ]; k]; Table[ a[n], {n, 1, 16}]
%o (PARI) for(n=1,16,s=1; while(binomial(2*s,s)%n!>0,s++); print1(s,","))
%K nonn
%O 1,3
%A _Benoit Cloitre_, Jun 19 2002
%E Edited and extended by _Robert G. Wilson v_, Jun 21 2002
%E More terms from _Naohiro Nomoto_, Jun 26 2002
%E More terms from _Don Reble_, Jul 01 2002