a(n) = n*Fibonacci(n) + binomial(n, 2).

Terms

a(0) =1a(1) =3a(2) =9a(3) =18a(4) =35a(5) =63a(6) =112a(7) =196a(8) =342a(9) =595a(10) =1034a(11) =1794a(12) =3107a(13) =5369a(14) =9255a(15) =15912a(16) =27285a(17) =46665a(18) =79610a(19) =135490a(20) =230076a(21) =389873a(22) =659364a(23) =1113108a(24) =1875925a(25) =3156543a(26) =5303637a(27) =8899086a(28) =14913047a(29) =24961635