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A100312 Number of 3 X n binary matrices avoiding simultaneously the right angled numbered polyomino patterns (ranpp) (10;0) and (01;1). An occurrence of a ranpp (xy;z) in a matrix A=(a(i,j)) is a triple (a(i1,j1), a(i1,j2), a(i2,j1)) where i1<i2, j1<j2 and these elements are in the same relative order as those in the triple (x,y,z). In general, the number of m X n 0-1 matrices in question is given by the g.f. 2xy/(1-2(x+y-xy)). 1
8, 32, 104, 304, 832, 2176, 5504, 13568, 32768, 77824, 182272, 421888, 966656, 2195456, 4947968, 11075584, 24641536, 54525952, 120061952, 263192576, 574619648, 1249902592, 2709520384, 5855248384 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

S. Kitaev, On multi-avoidance of right angled numbered polyomino patterns, Integers: Electronic Journal of Combinatorial Number Theory 4 (2004), A21, 20pp.

FORMULA

G.f.: 8*x*(1-x)^2/(1-2*x)^3

(n^2 + 5n + 2) * 2^(n-1).

CROSSREFS

Equals 8 * A049611(n).

Cf. m=4: A100313.

Sequence in context: A195590 A071345 A178797 * A204643 A003201 A036393

Adjacent sequences:  A100309 A100310 A100311 * A100313 A100314 A100315

KEYWORD

nonn

AUTHOR

Sergey Kitaev (kitaev(AT)ms.uky.edu), Nov 13 2004

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.