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A069325 Number of 3 X n binary arrays with path of adjacent 1's from upper right corner to lower left corner. 20
1, 8, 51, 295, 1632, 8830, 47239, 251261, 1332456, 7055228, 37327007, 197404203, 1043751584, 5518106750, 29171471659, 154210451661, 815197197636, 4309313949364, 22779900825195, 120418887728947 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..1383

Index entries for linear recurrences with constant coefficients, signature (9,-21,3,24,-8,-4,4).

FORMULA

G.f.: x*(1-x+x^3)/((1-2*x-2*x^2)*(2*x^5-4*x^4+x^3+9*x^2-7*x+1)). - Vladeta Jovovic, Jul 02 2003

MATHEMATICA

CoefficientList[Series[x*(1-x+x^3)/((1-2*x-2*x^2)*(2*x^5-4*x^4+x^3+9*x^2 -7*x+1)), {x, 0, 50}], x] (* G. C. Greubel, Apr 22 2018 *)

PROG

(PARI) Vec(-x*(1-x+x^3)/(2*x^2+2*x-1)/(2*x^5-4*x^4+x^3+9*x^2-7*x+1) + O(x^99)) \\ Charles R Greathouse IV, Jun 12 2015

(MAGMA) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(x*(1-x+x^3)/((1-2*x-2*x^2)*(2*x^5-4*x^4+x^3+9*x^2-7*x+1)))); // G. C. Greubel, Apr 22 2018

CROSSREFS

Cf. 2 X n A048739, 4 X n A069326, 5 X n A069327, 6 X n A069328, 7 X n A069329, 8 X n A069330, 9 X n A069331, 10 X n A069332, 11 X n A069333, 12 X n A069334, 13 X n A069335, 14 X n A069336, 15 X n A069337, 16 X n A069338, 17 X n A069339, 18 X n A069340, 19 X n A069341, 20 X n A069342, n X n A069343, n X n symmetric A069344.

Sequence in context: A054620 A034516 A240360 * A295348 A082135 A153594

Adjacent sequences:  A069322 A069323 A069324 * A069326 A069327 A069328

KEYWORD

nonn,easy

AUTHOR

R. H. Hardin, Mar 16 2002

STATUS

approved

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Last modified July 15 16:29 EDT 2019. Contains 325049 sequences. (Running on oeis4.)