a(n) = 3*a(n-1) + A001651(n+1).

Terms

a(0) =1a(1) =5a(2) =19a(3) =62a(4) =193a(5) =587a(6) =1771a(7) =5324a(8) =15985a(9) =47969a(10) =143923a(11) =431786a(12) =1295377a(13) =3886151a(14) =11658475a(15) =34975448a(16) =104926369a(17) =314779133a(18) =944337427a(19) =2833012310a(20) =8499036961a(21) =25497110915a(22) =76491332779a(23) =229473998372a(24) =688421995153