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Sum of exponents in prime-power factorization of binomial(6n, 3n).
11

%I #17 Nov 12 2017 06:08:21

%S 3,5,6,7,11,11,12,13,14,15,16,15,19,20,21,22,23,23,22,25,29,25,29,28,

%T 31,32,30,31,34,34,35,35,36,36,38,38,41,41,41,40,46,44,43,44,44,46,47,

%U 46,47,50,51,49,53,49,52,53,53,56,55,56,60,60,61,57,61,61,61,65,66,63,67,66,69,69,66,69,71,70,72,72

%N Sum of exponents in prime-power factorization of binomial(6n, 3n).

%H Ivan Neretin, <a href="/A023854/b023854.txt">Table of n, a(n) for n = 1..10000</a>

%t Total[Transpose[FactorInteger[Binomial[6 #,3 #]]][[2]]]&/@Range[80] (* _Harvey P. Dale_, May 14 2011 *)

%Y Cf. A023852, A023853.

%K nonn

%O 1,1

%A _Clark Kimberling_

%E Corrected and extended by _Harvey P. Dale_, May 14 2011