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A181258 Number of (n+2)X6 binary matrices with every 3X3 block having exactly four 1's 1
2484, 3942, 6360, 10818, 22512, 48846, 112500, 289830, 764832, 2072106, 5854728, 16700214, 48109644, 140771982, 413533560, 1219726098, 3620006112, 10762255326, 32052060900, 95704407030, 285982189392, 855223829946, 2560357197048 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A181262

LINKS

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

FORMULA

Empirical: a(n)=4*a(n-1)-3*a(n-2)+36*a(n-3)-144*a(n-4)+108*a(n-5)-503*a(n-6)+2012*a(n-7)-1509*a(n-8)+3480*a(n-9)-13920*a(n-10)+10440*a(n-11)-12564*a(n-12)+50256*a(n-13)-37692*a(n-14)+22464*a(n-15)-89856*a(n-16)+67392*a(n-17)-15552*a(n-18)+62208*a(n-19)-46656*a(n-20)

EXAMPLE

Some solutions for 4X6

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

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

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

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

CROSSREFS

Sequence in context: A235763 A235546 A214477 * A258442 A255750 A255757

Adjacent sequences:  A181255 A181256 A181257 * A181259 A181260 A181261

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 10 2010

STATUS

approved

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Last modified May 26 04:43 EDT 2022. Contains 354074 sequences. (Running on oeis4.)