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A265062 Coordination sequence for (2,4,7) tiling of hyperbolic plane. 27
1, 3, 5, 8, 12, 17, 25, 36, 50, 70, 98, 137, 193, 271, 379, 531, 744, 1042, 1461, 2048, 2869, 4020, 5633, 7893, 11061, 15500, 21719, 30434, 42646, 59758, 83738, 117340, 164424, 230402, 322855, 452406, 633943, 888325, 1244781, 1744272, 2444193, 3424970, 4799303, 6725112, 9423686, 13205113, 18503907, 25928939, 36333403 (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+1)^2*(x^2+1)*(x^6+x^5+x^4+x^3+x^2+x+1)/(x^10-x^7-x^6-x^5-x^4-x^3+1).

MATHEMATICA

CoefficientList[Series[(x + 1)^2 (x^2 + 1) (x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)/(x^10 - x^7 - x^6 - x^5 - x^4 - x^3 + 1), {x, 0, 50}], x] (* Vincenzo Librandi, Dec 31 2015 *)

PROG

(PARI) Vec((x+1)^2*(x^2+1)*(x^6+x^5+x^4+x^3+x^2+x+1)/(x^10-x^7-x^6-x^5-x^4-x^3+1) + O(x^50)) \\ Michel Marcus, Dec 31 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: A018917 A167385 A265061 * A265063 A098202 A164653

Adjacent sequences:  A265059 A265060 A265061 * A265063 A265064 A265065

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 29 2015

STATUS

approved

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Last modified April 22 22:19 EDT 2021. Contains 343197 sequences. (Running on oeis4.)