OFFSET
1,2
COMMENTS
a(10^n) =0 = a(10k+5),if 10k + 5 is not==0 (mod 25). Are there any other numbers r such that a(r) =0?
EXAMPLE
a(14) = 0 because any number ending in 14 is even but not divisible by 4 and any even power is divisible by 4. [From David Wasserman, Jan 15 2009]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Aug 03 2005
EXTENSIONS
Corrected and extended by David Wasserman, Jan 15 2009
STATUS
approved