A321852 a(n) is the smallest m for which binomial(m, 6) has exactly n distinct prime factors.

6, 7, 8, 9, 10, 18, 26, 40, 77, 120, 210, 477, 715, 2227, 3290, 9065, 17020, 49915, 139195, 240465, 721929, 1124840, 4455445, 16319578, 26683220, 105655905, 134879176, 677868170, 3290262264

Offset: 0

Author

Zachary M Franco, Nov 19 2018

Keywords

• nonn
• more

Crossrefs

Cf. A076551, A156329.

Programs

Mathematica

a[n_] := Module[{m=6, t=1}, While[PrimeNu[t] != n, m++; t*=m/(m-6)]; m]; Array[a, 20] (* Amiram Eldar, Nov 27 2018 *)

PARI

a(n)={my(m=6, t=1); while(omega(t)<>n, m++; t*=m/(m-6)); m} \\ Andrew Howroyd, Nov 26 2018

Extensions

a(22)-a(28) from Giovanni Resta, Nov 27 2018

a(0) prepended by Jianing Song, Dec 31 2018