|
%I #9 Apr 07 2014 03:36:41
%S 0,0,0,0,0,0,0,0,0,1,1,2,1,0,3,3,1,1,0,2,4,5,2,2,4,2,1,8,3,7,9,4,4,6,
%T 5,3,8,2,8,3,9,6,4,6,8,7,7,4,12,4,15,10,10,9,13,10,15,7,7,19,15,9,20,
%U 12,11,12,15,19,12,15,20,10,12,13,13,19,16,13,21,17,17,23,19,13,13,15,18
%N Number of 4's in n# (n primorial) = 4's in A002110(n).
%H Vincenzo Librandi, <a href="/A079123/b079123.txt">Table of n, a(n) for n = 2..1000</a>
%t Count[IntegerDigits[#], 4]&/@FoldList[Times, 1, Prime[Range[90]]] (* _Harvey P. Dale_, Oct 12 2011 *)
%o (PARI) See program in Number of 0's in n#
%Y Cf. A002110.
%K easy,nonn
%O 2,12
%A _Cino Hilliard_, Feb 03 2003
|
