OFFSET
0,2
COMMENTS
LINKS
Max Alekseyev, Table of n, a(n) for n = 0..1000
EXAMPLE
a(1) = #{2^1 - 3^0, 2^2 - 3^1, 3^1 - 2^1, 3^2 - 2^3} = 4;
a(2) = #{3^1 - 2^0} = 1;
a(3) = #{2^2 - 3^0} = 1;
a(5) = #{2^3 - 3^1, 2^5 - 3^3, 3^2 - 2^2} = 3;
a(7) = #{2^3 - 3^0, 2^4 - 3^2, 3^2 - 2^1} = 3;
a(8) = #{3^2 - 2^0} = 1;
a(11) = #{3^3 - 2^4} = 1;
a(13) = #{2^4 - 3^1, 2^8 - 3^5} = 2;
a(15) = #{2^4 - 2^0} = 1;
a(17) = #{3^4 - 2^6} = 1;
a(19) = #{3^3 - 2^3} = 1;
a(23) = #{2^5 - 3^2, 3^3 - 2^2} = 2;
a(25) = #{3^3 - 2^1} = 1.
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 25 2007
STATUS
approved