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A207948 Number of nX7 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically 1
20, 400, 2340, 18330, 133812, 1007146, 7513176, 56114310, 418757982, 3126019338, 23335656728, 174203347410, 1300429210274, 9707701033916, 72467964696512, 540973578440920, 4038369684995910, 30146442775842786, 225043284353552098 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207949

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) +3*a(n-2) +8*a(n-3) +303*a(n-4) +385*a(n-5) +871*a(n-6) +4356*a(n-7) +5282*a(n-8) +3375*a(n-9) +4096*a(n-10) -4422*a(n-11) -32005*a(n-12) -63696*a(n-13) -35314*a(n-14) +48358*a(n-15) +111187*a(n-16) +82219*a(n-17) -21414*a(n-18) -76099*a(n-19) -68521*a(n-20) -1500*a(n-21) +23855*a(n-22) +27908*a(n-23) +3257*a(n-24) -2887*a(n-25) -6127*a(n-26) -714*a(n-27) -94*a(n-28) +735*a(n-29) +43*a(n-30) +42*a(n-31) -45*a(n-32) -2*a(n-34) +a(n-35)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207402 A207751 A207127 * A206938 A208141 A188603

Adjacent sequences:  A207945 A207946 A207947 * A207949 A207950 A207951

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 21 2012

STATUS

approved

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Last modified December 8 16:57 EST 2021. Contains 349596 sequences. (Running on oeis4.)