A137531 a(n) = 3*a(n-1) - 2*a(n-2) + a(n-3).

1, 4, 10, 23, 53, 123, 286, 665, 1546, 3594, 8355, 19423, 45153, 104968, 244021, 567280, 1318766, 3065759, 7127025, 16568323, 38516678, 89540413, 208156206, 483904470, 1124941411, 2615171499, 6079536145, 14133206848, 32855719753, 76380281708, 177562612466

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (3,-2,1).

Formula

G.f.: (1 + x) / (1 - 3*x + 2*x^2 - x^3). - Colin Barker, Feb 17 2017

Mathematica

LinearRecurrence[{3, -2, 1}, {1, 4, 10}, 100] (* G. C. Greubel, Feb 17 2017 *)

Prog

(PARI) a=[1, 4, 10]; for(i=1, 99, a=concat(a, 3*a[#a]-2*a[#a-1]+a[#a-2])); a \\ Charles R Greathouse IV, Jun 01 2011
(PARI) Vec((1 + x) / (1 - 3*x + 2*x^2 - x^3) + O(x^40)) \\ Colin Barker, Feb 17 2017

Crossrefs

Cf. A159347, A097550.

Sequence in context: A118645 A200759 A159347 * A102549 A277789 A274019

Adjacent sequences: A137528 A137529 A137530 * A137532 A137533 A137534

Keyword

nonn,easy

Author

Paul Curtz, Apr 25 2008

Extensions

More terms from Vladimir Joseph Stephan Orlovsky, Jan 20 2009

Status

approved