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a(n) is the smallest m for which binomial(m, 6) has exactly n distinct prime factors.
1

%I #26 Jan 10 2019 10:26:38

%S 6,7,8,9,10,18,26,40,77,120,210,477,715,2227,3290,9065,17020,49915,

%T 139195,240465,721929,1124840,4455445,16319578,26683220,105655905,

%U 134879176,677868170,3290262264

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

%t 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 *)

%o (PARI) a(n)={my(m=6, t=1); while(omega(t)<>n, m++; t*=m/(m-6)); m} \\ _Andrew Howroyd_, Nov 26 2018

%Y Cf. A076551, A156329.

%K nonn,more

%O 0,1

%A _Zachary M Franco_, Nov 19 2018

%E a(22)-a(28) from _Giovanni Resta_, Nov 27 2018

%E a(0) prepended by _Jianing Song_, Dec 31 2018