%I A072831
%S A072831 1,1,2,3,5,7,10,13,16,19,22,26,29,33,37,41,45,49,53,57,62,66,70,75,80,
%T A072831 84,89,94,98,103,108,113,118,123,128,133,139,144,149,154,160,165,170,
%U A072831 176,181,187,192,198,203,209,215,220,226,232,238,243,249,255,261,267
%N A072831 Number of bits in n!.
%F A072831 a(n) = floor(log(n!)/log(2)) + 1.
%e A072831 a(4)=5 because 4! = 4*3*2*1 = 24 (base 10) = 11000 (base 2), using 5 
               bits.
%o A072831 (PARI) for(n=0,100,print1(floor(log(n!)/log(2))+1,","))
%Y A072831 Cf. A034886 (decimal digits of n!), A000142 (n!). Essentially the same 
               as A003070.
%Y A072831 Sequence in context: A064509 A096221 A120367 this_sequence A072388 A101433 
               A024180
%Y A072831 Adjacent sequences: A072828 A072829 A072830 this_sequence A072832 A072833 
               A072834
%K A072831 base,nonn
%O A072831 0,3
%A A072831 Rick L. Shepherd (rshepherd2(AT)hotmail.com), Jul 22 2002