

A322158


a(n) is the smallest m for which binomial(m,5) has exactly n distinct prime factors.


0



6, 9, 11, 22, 25, 70, 78, 276, 497, 990, 1771, 8178, 20504, 44254, 181051, 416328, 1013728, 3383579, 8667726, 34332376, 122289552, 244215150, 969751302, 1865174676, 6648863728, 26888317326, 107132035803
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OFFSET

2,1


COMMENTS

Binomial(m,5) is never prime, so the offset is 2.


LINKS

Table of n, a(n) for n=2..28.


MATHEMATICA

a[n_] := Module[{m = 5}, While[PrimeNu[Binomial[m, 5]] != n, m++]; m]; Array[a, 10, 2] (* Amiram Eldar, Nov 29 2018 *)


PROG

(PARI) a(n) = for(m=5, oo, if(omega(binomial(m, 5))==n, return(m))) \\ Felix FrÃ¶hlich, Dec 01 2018


CROSSREFS

Cf. A005733, A005735, A321852.
Sequence in context: A084418 A226133 A125971 * A143710 A087022 A315951
Adjacent sequences: A322155 A322156 A322157 * A322159 A322160 A322161


KEYWORD

nonn,more


AUTHOR

Zachary M Franco, Nov 27 2018


EXTENSIONS

a(22)a(23) from Chai Wah Wu, Dec 29 2018
a(24)a(28) from Giovanni Resta, Jan 04 2019


STATUS

approved



