OFFSET
0,3
EXAMPLE
floor(e^3) = floor(20.08553) = 20. 20 has two distinct prime factors (2 and 5), therefore a(3) = 2.
MATHEMATICA
Table[Length[FactorInteger[Floor[E^n]]], {n, 1, 80}]
PrimeNu[Floor[E^Range[80]]] (* Harvey P. Dale, Jul 21 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefan Steinerberger, Feb 17 2006
STATUS
approved