%I #7 Dec 15 2017 17:36:44
%S 1,1,3,4,4,4,4,6,6,1,6,5,10,5,16,14,12,17,22,4,9,21,21,22,18,25,22,21,
%T 15,4,27,28,29,23,32,34,39,38,52,13,45,56,50,53,27,50,44,48,47,18,48,
%U 62,42,47,48,44,57,67,58,31,71,66,63,57,71,67,56,74,70,42,100,89,72,60,75
%N Number of 1's in binary expansion(product of nonzero digits(n^n)).
%C Conjecture: a(n) = a(n+1) for infinitely many positive integers. Largest found is n=1091, i.e. n1b(pnd(1091^1091)) = n1b(pnd(1092^1092)) = 1892.
%t Table[Count[IntegerDigits[Times@@DeleteCases[IntegerDigits[n^n],0],2],1],{n,80}] (* _Harvey P. Dale_, Mar 08 2017 *)
%Y Cf. A000120, A051801.
%K base,easy,nonn
%O 0,3
%A _Jason Earls_, Jun 29 2004