0,5

a(n) = SUM(A010052(A007318(n,k)): 0<=k<=n/2);

a(A000290(n)) > 1 for n>1.

a(8) = #{1} = 1;

a(9) = #{1,9,36} = 3.

Sequence in context: A125761 A060990 A154950 this_sequence A056926 A137773 A107454

Adjacent sequences: A158461 A158462 A158463 this_sequence A158465 A158466 A158467

nonn

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Mar 19 2009