A203245 Second elementary symmetric function of the first n terms of (1,2,3,5,8,...).

2, 11, 41, 129, 376, 1048, 2850, 7635, 20273, 53537, 140912, 370128, 970978, 2545243, 6668697, 17467233, 45743336, 119779496, 313622210, 821130915, 2149841377, 5628507841, 14735867616, 38579395104, 101002803266, 264429800363

Offset: 1

Author

Clark Kimberling, Dec 31 2011

Keywords

• nonn

Crossrefs

Cf. A190173.

Programs

Mathematica

f[k_] := Fibonacci[k + 1]; t[n_] := Table[f[k], {k, 1, n}]
a[n_] := SymmetricPolynomial[2, t[n]]
Table[a[n], {n, 2, 32}]  (* A203245 *)

Formula

Empirical g.f.: -x*(x^3-x^2-3*x-2) / ((x-1)*(x+1)*(x^2-3*x+1)*(x^2+x-1)). - Colin Barker, Aug 15 2014