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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 (list; graph; refs; listen; history; text; internal format)
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 Fröhlich, 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

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Last modified January 20 10:09 EST 2022. Contains 350471 sequences. (Running on oeis4.)