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A188517 Number of nX3 binary arrays without the pattern 1 1 0 diagonally, vertically or horizontally 1
7, 49, 229, 1016, 4143, 16438, 63575, 242843, 918833, 3457086, 12955090, 48421778, 180653858, 673156166, 2506152176, 9324771027, 34680539851, 128945324565, 479330913137, 1781567026168, 6621013690288, 24604558144729, 91429145674242 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A188523

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=7*a(n-1)-5*a(n-2)-54*a(n-3)+79*a(n-4)+173*a(n-5)-294*a(n-6)-313*a(n-7)+521*a(n-8)+357*a(n-9)-501*a(n-10)-255*a(n-11)+272*a(n-12)+106*a(n-13)-84*a(n-14)-23*a(n-15)+14*a(n-16)+2*a(n-17)-a(n-18).

Empirical: G.f. -x*(-7 +79*x^2 -36*x^3 -269*x^4 +199*x^5 +422*x^6 -446*x^7 -410*x^8 +468*x^9 +269*x^10 -264*x^11 -109*x^12 +84*x^13 +23*x^14 -14*x^15 -2*x^16 +x^17) / ( (x-1) *(x^2-3*x+1) *(x^2-x-1) *(x^3-2*x^2-x+1) *(x^4+x^3-3*x^2-3*x+1) *(1+x)^2 *(x^2+x-1)^2 ). - R. J. Mathar, Dec 21 2011

EXAMPLE

Some solutions for 4X3

..0..0..0....1..0..1....1..0..1....0..1..0....1..0..0....0..0..1....0..0..1

..0..1..0....0..1..0....0..0..0....0..0..0....0..1..0....0..1..0....0..1..0

..0..0..0....1..1..1....0..1..1....0..1..0....0..0..1....1..0..0....0..0..1

..0..1..0....0..1..1....1..0..1....0..0..0....0..0..1....1..1..1....0..1..1

CROSSREFS

Sequence in context: A188845 A223632 A188502 * A206878 A206780 A181219

Adjacent sequences:  A188514 A188515 A188516 * A188518 A188519 A188520

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 02 2011

STATUS

approved

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Last modified January 27 22:46 EST 2022. Contains 350654 sequences. (Running on oeis4.)