a(n) = 2^n + 3^n + 6^n - 1.

Terms

a(0) =10a(1) =48a(2) =250a(3) =1392a(4) =8050a(5) =47448a(6) =282250a(7) =1686432a(8) =10097890a(9) =60526248a(10) =362976250a(11) =2177317872a(12) =13062296530a(13) =78368963448a(14) =470199366250