%I #7 May 15 2017 03:06:17
%S 0,2,1,2,1,3,2,2,3,3,2,3,2,4,2,2,2,5,3,3,4,4,1,3,3,4,3,4,2,4,2,2,2,4,
%T 4,5,3,5,3,3,3,6,2,4,4,3,1,3,3,5,3,4,2,5,2,4,2,4,2,4,2,4,5,2,2,4,2,4,
%U 2,6,2,5,2,5,4,5,2,5,2,3,2,5,2,6,3,4,2,4,1,6,3,3,4,3,4,3,3,5,2,5,1,5,2,4,3
%N Number of distinct prime factors of numbers containing in their decimal representation only the digits 0 and 1.
%H G. C. Greubel, <a href="/A077807/b077807.txt">Table of n, a(n) for n = 1..5000</a>
%F a(n) = A001221(A007088(n)).
%e a(36) = A001221(A007088(36)) = A001221(100100) = A001221(2*2*5*5*7*11*13) = 5.
%t Table[PrimeNu[FromDigits[IntegerDigits[n, 2]]], {n, 1, 50}] (* _G. C. Greubel_, May 14 2017 *)
%o (PARI) for(n=1, 50, print1(omega(fromdigits(binary(n), 10)), ", ")) \\ _G. C. Greubel_, May 14 2017
%Y Cf. A077808.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, Nov 16 2002