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%I #5 Apr 30 2014 01:27:35
%S 3,7,399,759,971,52947,133663,144027,7011591,18280739,24294831,
%T 926780523,2486418967,3842160243,122290016319,336572174651,
%U 583349245479,16110885760707,45370056714703,86112795218187,2119413836354871
%N Integers where 3^n and 5^m are nearly the same gives a difference sequence.
%C 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.
%F a(q) = if 3^n>5^m and Floor[3^n/5^m]<2 then a[q]=Abs[3^n-5^m]
%t 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]
%K nonn,uned
%O 1,1
%A _Roger L. Bagula_, Mar 01 2005
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