OFFSET
1,1
COMMENTS
Sequence appears trisected: a(3m+3) = 2^(7m+3)-5^(3m+1), m>0; a(3m+1) = 2^(7m+5)-5^(3m+2), m>1; a(3m+2) = 2^(7m+7)-5^(3m+3), m>1. -- Ralf Stephan, Nov 13 2010.
FORMULA
a(q) = if 3^n>5^m and Floor[3^n/5^m]<2 then a[q]=Abs[3^n-5^m]
MATHEMATICA
c = Delete[Union[Flatten[Table[Table[If [ (2^n > 5^m) && Floor[2^n/5^m] < 2, Abs[2^n - 5^m], 0], {m, 1, n}], {n, 1, 200}], 1]], 1]
CROSSREFS
KEYWORD
nonn,uned
AUTHOR
Roger L. Bagula, Mar 01 2005
STATUS
approved