A234273 G.f.: (1+x+x^2+x^3)/(1-x^2-2*x^3-x^4+x^6).

1, 1, 2, 4, 5, 9, 14, 22, 35, 55, 88, 138, 219, 347, 548, 868, 1373, 2173, 3438, 5440, 8609, 13621, 21554, 34106, 53967, 85395, 135124, 213814, 338327, 535351, 847112, 1340424, 2121017, 3356185, 5310650, 8403292, 13296925, 21040353, 33293142, 52681310, 83360123, 131904655, 208718960, 330265858, 522595251

Offset

0,3

Links

Table of n, a(n) for n=0..44.

J. Choi, N. Pippenger, Counting the Angels and Devils in Escher's Circle Limit IV, arXiv preprint arXiv:1310.1357 [math.CO], 2013.

Index entries for linear recurrences with constant coefficients, signature (0, 1, 2, 1, 0, -1).

Mathematica

LinearRecurrence[{0, 1, 2, 1, 0, -1}, {1, 1, 2, 4, 5, 9}, 45] (* Jean-François Alcover, Feb 12 2019 *)

Crossrefs

Sequence in context: A077882 A351293 A363225 * A120939 A213290 A277852

Adjacent sequences: A234270 A234271 A234272 * A234274 A234275 A234276

Keyword

nonn

Author

N. J. A. Sloane, Dec 24 2013

Status

approved