%I A065352
%S A065352 1,3,8,19,42,153,216,375,950,3565,4068,12273,12274,31729,122352
%N A065352 Smallest m such that C(2m,m) is divisible by (m+n)!/m!.
%C A065352 For n=1 see Catalan-numbers:A000108.
%F A065352 C(2m, m)=A*((m+1)(m+2)...(m+n-1)(m+n)); a(n) is the smallest such m belonging
to n: a(n)=Min(m; Mod(A000984(m), (m+n)!/m!)=0)
%e A065352 n=4: a(4)=19 means that C(38,19)=35345263800 is divisible by (19+1)(19+2)(19+3)(19+4)=23!/
19!=20.21.22.23=215520; the quotient is 166315. Smaller (<19) central
binomial coefficients are not divisible by such a product of 4 successive
terms; the corresponding quotients for n=1,2,3,4,5,... are 1,1,13,
166315,9120910752273999,...
%Y A065352 Cf. A065344-A065350, A002503, A000108, A000984.
%Y A065352 Sequence in context: A095681 A079583 A099050 this_sequence A161993 A008466
A102712
%Y A065352 Adjacent sequences: A065349 A065350 A065351 this_sequence A065353 A065354
A065355
%K A065352 nonn
%O A065352 1,2
%A A065352 Labos E. (labos(AT)ana.sote.hu), Oct 31 2001
%E A065352 More terms from Naohiro Nomoto (n_nomoto(AT)yabumi.com), Apr 21 2002
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