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A207767 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically 1
31, 961, 2305, 17563, 67330, 178627, 887114, 3733566, 11979209, 49800326, 208738438, 742476229, 2900533473, 11843654162, 44397947317, 170655647841, 681016789541, 2614418854083, 10044216333681, 39503065976101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207762

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 3*a(n-1) -3*a(n-2) +75*a(n-3) -165*a(n-4) +117*a(n-5) -1993*a(n-6) +3819*a(n-7) -1872*a(n-8) +28120*a(n-9) -52719*a(n-10) +21633*a(n-11) -245836*a(n-12) +475386*a(n-13) -202047*a(n-14) +1424731*a(n-15) -2854572*a(n-16) +1336596*a(n-17) -5595456*a(n-18) +11419032*a(n-19) -5756664*a(n-20) +14788744*a(n-21) -30146304*a(n-22) +15765936*a(n-23) -25534368*a(n-24) +51292992*a(n-25) -27030768*a(n-26) +27214704*a(n-27) -53527680*a(n-28) +27914688*a(n-29) -16039296*a(n-30) +30855168*a(n-31) -15780096*a(n-32) +3960576*a(n-33) -7464960*a(n-34) +3732480*a(n-35) for n>37

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A200442 A207777 A207274 * A207734 A208693 A207563

Adjacent sequences:  A207764 A207765 A207766 * A207768 A207769 A207770

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 19 2012

STATUS

approved

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Last modified September 16 20:51 EDT 2021. Contains 347473 sequences. (Running on oeis4.)