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A265057 Coordination sequence for (2,3,7) tiling of hyperbolic plane. 27
1, 3, 5, 7, 9, 12, 16, 20, 24, 28, 33, 40, 48, 57, 67, 78, 92, 109, 129, 152, 178, 209, 246, 290, 342, 402, 472, 555, 653, 769, 905, 1064, 1251, 1471, 1731, 2037, 2396, 2818, 3314, 3898, 4586, 5395, 6346, 7464, 8779, 10327, 12148, 14290, 16809, 19771, 23256, 27356, 32179, 37852, 44524, 52372 (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^6+x^5+x^4+x^3+x^2+x+1)*(x^2+x+1)*(x+1)^2/(x^10+x^9-x^7-x^6-x^5-x^4-x^3+x+1).

MATHEMATICA

CoefficientList[Series[(x^6 + x^5 + x^4 + x^3 + x^2 + x + 1) (x^2 + x + 1) (x + 1)^2/(x^10 + x^9 - x^7 - x^6 - x^5 - x^4 - x^3 + x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)

PROG

(PARI) x='x+O('x^50); Vec((x^6+x^5+x^4+x^3+x^2+x+1)*(x^2+x+1)*(x+1)^2/(x^10+x^9-x^7-x^6-x^5-x^4-x^3+x+1)) \\ G. C. Greubel, Aug 06 2017

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: A226331 A316312 A118015 * A122643 A194240 A265058

Adjacent sequences:  A265054 A265055 A265056 * A265058 A265059 A265060

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Dec 29 2015

STATUS

approved

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Last modified December 10 05:49 EST 2018. Contains 318044 sequences. (Running on oeis4.)