2,2

(1/3!)*(11-6*3^n+7^n).

Column of A055154.

Sequence in context: A096764 A165004 A165008 this_sequence A087342 A083468 A125395

Adjacent sequences: A095149 A095150 A095151 this_sequence A095153 A095154 A095155

easy,nonn

Vladeta Jovovic (vladeta(AT)eunet.rs), May 31 2004