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Sum of exponents in prime-power factorization of C(3n,n).
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%I #12 Nov 02 2017 17:51:30

%S 1,2,4,4,4,6,8,6,7,8,11,11,11,11,12,10,12,11,15,13,13,18,18,17,16,17,

%T 19,17,18,19,22,18,18,20,21,19,21,22,23,22,21,23,28,27,27,28,30,27,28,

%U 26,28,29,28,31,32,29,31,31,35,32,33,35,34,31,30,31,34,31,32,35,36,33,34,35,38,37,36,36

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

%C Equivalently, sum of exponents of primes in multinomial coefficient M(3n; n,n,n)/C(2n,n).

%H Ivan Neretin, <a href="/A023819/b023819.txt">Table of n, a(n) for n = 1..10000</a>

%p with(numtheory):(combinat):a:=proc(n) if n=0 then 0 else bigomega(binomial(3*n,n)) fi end: seq(a(n), n=1..78); # _Zerinvary Lajos_, Apr 11 2008

%t Table[Total[FactorInteger[Binomial[3 n, n]][[All, 2]]], {n, 78}] (* _Ivan Neretin_, Nov 02 2017 *)

%K nonn

%O 1,2

%A _Clark Kimberling_

%E Edited by _N. J. A. Sloane_ at the suggestion of _R. J. Mathar_, May 31 2008