1,1

a(n) = 9*8^((n-1)/2)-2 (n odd), 2*8^(n/2)-2 (n even).

Cf. A050250.

Sequence in context: A135536 A020700 A110496 this_sequence A143682 A080451 A061522

Adjacent sequences: A117864 A117865 A117866 this_sequence A117868 A117869 A117870

nonn

Martin Renner (martin.renner(AT)gmx.net), May 02 2006