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A265069 Coordination sequence for (2,6,6) tiling of hyperbolic plane. 27
1, 3, 5, 8, 13, 21, 32, 47, 71, 108, 163, 245, 368, 555, 837, 1260, 1897, 2857, 4304, 6483, 9763, 14704, 22147, 33357, 50240, 75667, 113965, 171648, 258525, 389373, 586448, 883271, 1330327, 2003652, 3017771, 4545173, 6845648, 10310475, 15528973, 23388740, 35226617, 53056065, 79909632, 120354747, 181270579, 273018088 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

J. W. Cannon, P. Wagreich, Growth functions of surface groups, Mathematische Annalen, 1992, Volume 293, pp. 239-257. See Prop. 3.1.

FORMULA

G.f.: (x^5+x^4+x^3+x^2+x+1)*(x+1)/(x^6-x^5-x^3-x+1).

MATHEMATICA

CoefficientList[Series[(x^5 + x^4 + x^3 + x^2 + x + 1) (x + 1)/(x^6 - x^5 - x^3 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)

PROG

(PARI) Vec((x^5+x^4+x^3+x^2+x+1)*(x+1)/(x^6-x^5-x^3-x+1) + O(x^50)) \\ Michel Marcus, Dec 30 2015

CROSSREFS

Coordination sequences for triangular tilings of hyperbolic space: A001630, A007283, A054886, A078042, A096231, A163876, A179070, A265057, A265058, A265059, A265060, A265061, A265062, A265063, A265064, A265065, A265066, A265067, A265068, A265069, A265070, A265071, A265072, A265073, A265074, A265075, A265076, A265077.

Sequence in context: A163685 A080614 A079122 * A265070 A071679 A020701

Adjacent sequences:  A265066 A265067 A265068 * A265070 A265071 A265072

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Dec 29 2015

STATUS

approved

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Last modified November 15 04:00 EST 2018. Contains 317225 sequences. (Running on oeis4.)