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Sum of exponents in prime-power factorization of C(4n,n+3).
1

%I #8 Nov 08 2017 16:03:27

%S 0,4,5,7,6,8,8,11,11,12,11,12,10,15,13,17,15,17,16,18,18,20,17,20,19,

%T 21,21,21,18,22,20,26,22,26,25,27,25,28,28,30,29,31,30,31,28,28,27,33,

%U 30,33,31,33,30,35,30,34,33,35,36,35,33,37,37,42,38,41,39,42,41,44,39,45,42,45,46,45,44

%N Sum of exponents in prime-power factorization of C(4n,n+3).

%H Ivan Neretin, <a href="/A023833/b023833.txt">Table of n, a(n) for n = 1..10000</a>

%t Join[{0},Total[Transpose[FactorInteger[#]][[2]]]&/@Table[Binomial[4n,n+3],{n,2,80}]] (* _Harvey P. Dale_, Dec 24 2014 *)

%K nonn

%O 1,2

%A _Clark Kimberling_