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A023846
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Sum of exponents in prime-power factorization of binomial(5n, n+4).
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1
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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
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OFFSET
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1,2
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COMMENTS
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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
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LINKS
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MAPLE
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seq(numtheory:-bigomega(binomial(5*n, n+4)), n=1..100); # Robert Israel, Nov 09 2017
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MATHEMATICA
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Table[PrimeOmega[Binomial[5 n, n + 4]], {n, 77}] (* Ivan Neretin, Nov 09 2017 *)
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PROG
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(PARI) a(n) = a(n) = bigomega(binomial(5*n, n+4)); \\ Michel Marcus, Nov 09 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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