A023827 - OEIS

A023827

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

0, 3, 3, 6, 4, 7, 8, 10, 9, 11, 8, 11, 10, 15, 14, 16, 13, 16, 14, 18, 15, 17, 17, 21, 20, 21, 19, 20, 18, 22, 21, 26, 21, 26, 24, 27, 23, 26, 28, 28, 28, 30, 26, 30, 27, 29, 29, 33, 30, 33, 30, 33, 30, 33, 31, 33, 31, 33, 32, 36, 35, 39, 39, 42, 37, 40, 38, 41, 40, 42, 40, 44, 41, 45, 44, 46, 44, 46

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OFFSET

1,2

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000

MATHEMATICA

Join[{0}, Table[Total[Transpose[FactorInteger[Binomial[4n, n-1]]] [[2]]], {n, 2, 80}]] (* Harvey P. Dale, Jun 13 2013 *)

CROSSREFS

Sequence in context: A048149 A155169 A144624 * A199153 A182627 A135986

Adjacent sequences: A023824 A023825 A023826 * A023828 A023829 A023830

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved