1,1

a(n) = 3*4^floor((n-1)/2))

Cf. A050683.

Sequence in context: A066437 A065957 A032308 this_sequence A073055 A074850 A075780

Adjacent sequences: A117853 A117854 A117855 this_sequence A117857 A117858 A117859

nonn

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