A023850 Sum of exponents in prime-power factorization of binomial(5n, 2n+1).

2, 5, 5, 7, 9, 10, 11, 14, 13, 14, 14, 15, 17, 18, 19, 20, 19, 21, 18, 25, 26, 21, 24, 26, 25, 30, 28, 28, 31, 32, 31, 32, 32, 32, 33, 36, 34, 36, 38, 37, 37, 39, 33, 38, 40, 37, 39, 41, 40, 43, 43, 46, 49, 47, 47, 50, 46, 50, 47, 52, 52, 52, 52, 51, 53, 53, 48, 53, 57, 53, 57, 58, 56, 59, 58, 60

Offset

1,1

Links

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

Formula

a(n) = A023847(n) + A001222(3*n) - A001222(2*n+1). - Amiram Eldar, Jun 14 2025

Mathematica

Table[PrimeOmega[Binomial[5 n, 2 n + 1]], {n, 76}] (* Ivan Neretin, Nov 09 2017 *)

Prog

(PARI) a(n) = bigomega(binomial(5*n, 2*n+1)); \\ Amiram Eldar, Jun 14 2025

Crossrefs

Cf. A001222, A023837, A023839, A023840, A023841, A023842, A023843, A023844, A023845, A023846, A023847, A023848, A023849, A023851.

Sequence in context: A256300 A342852 A383361 * A175649 A240497 A142353

Adjacent sequences: A023847 A023848 A023849 * A023851 A023852 A023853

Keyword

nonn

Author

Clark Kimberling

Status

approved