login
Sum of exponents in prime-power factorization of C(2n,n-2).
1

%I #7 Nov 02 2017 17:50:42

%S 0,2,3,5,4,4,6,8,6,7,8,9,8,10,11,12,11,11,12,14,11,12,14,15,13,15,16,

%T 16,13,13,17,19,14,16,18,17,15,18,19,22,20,20,21,24,21,20,23,24,23,24,

%U 22,23,22,23,24,25,22,24,27,27,22,26,29,30,26,26,28,30,27,28,31,31,29,31,31,33,31,28,31

%N Sum of exponents in prime-power factorization of C(2n,n-2).

%H Ivan Neretin, <a href="/A023818/b023818.txt">Table of n, a(n) for n = 2..10000</a>

%t Join[{0}, Table[Total[FactorInteger[Binomial[2 n, n - 2]][[All, 2]]], {n, 3, 80}]] (* _Ivan Neretin_, Nov 02 2017 *)

%K nonn

%O 2,2

%A _Clark Kimberling_

%E Offset corrected to 2 by _Ivan Neretin_, Nov 02 2017