The sum of the Fibonacci and shifted tribonacci sequences.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =4a(5) =8a(6) =13a(7) =22a(8) =38a(9) =65a(10) =112a(11) =194a(12) =337a(13) =588a(14) =1030a(15) =1811a(16) =3196a(17) =5660a(18) =10057a(19) =17926a(20) =32046a(21) =57445a(22) =103236a(23) =185962a(24) =335697a(25) =607184a(26) =1100186a(27) =1996699a(28) =3629044a(29) =6604536