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A023846 Sum of exponents in prime-power factorization of binomial(5n, n+4). 1
0, 4, 5, 6, 6, 8, 10, 10, 10, 11, 12, 13, 15, 14, 14, 16, 15, 17, 16, 20, 19, 18, 18, 20, 19, 22, 25, 22, 23, 25, 24, 26, 24, 25, 24, 26, 25, 27, 30, 30, 28, 31, 29, 29, 31, 29, 31, 33, 32, 33, 33, 37, 36, 38, 39, 40, 38, 42, 40, 41, 40, 39, 39, 40, 39, 40, 39, 40, 43, 41, 43, 47, 43, 45, 47, 45, 46 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

By Kummer's theorem, a(n) is the sum over all primes p of the number of carries when n+4 is added to 4n-4 in base p. - Robert Israel, Nov 09 2017

LINKS

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

Wikipedia, Kummer's theorem

MAPLE

seq(numtheory:-bigomega(binomial(5*n, n+4)), n=1..100); # Robert Israel, Nov 09 2017

MATHEMATICA

Table[PrimeOmega[Binomial[5 n, n + 4]], {n, 77}] (* Ivan Neretin, Nov 09 2017 *)

PROG

(PARI) a(n) = a(n) = bigomega(binomial(5*n, n+4)); \\ Michel Marcus, Nov 09 2017

CROSSREFS

Cf. A023816-A023854.

Sequence in context: A162310 A116962 A273777 * A046345 A325103 A004445

Adjacent sequences:  A023843 A023844 A023845 * A023847 A023848 A023849

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified February 17 02:22 EST 2020. Contains 331976 sequences. (Running on oeis4.)