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A207728 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically 1
40, 1600, 6016, 33063, 211680, 1029231, 4799749, 23473944, 111527152, 517774120, 2415619129, 11251097760, 52094413065, 240990441237, 1114766044504, 5150494925352, 23781871171576, 109797744696883, 506801727014800 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207729

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -7*a(n-2) +31*a(n-3) -128*a(n-4) -30*a(n-5) -116*a(n-6) +788*a(n-7) +798*a(n-8) +678*a(n-9) -2778*a(n-10) -1872*a(n-11) -1842*a(n-12) +3336*a(n-13) +1554*a(n-14) +378*a(n-15) -2736*a(n-16) +912*a(n-17) +312*a(n-18) +1590*a(n-19) -540*a(n-20) -228*a(n-21) -222*a(n-22) +210*a(n-23) -86*a(n-24) +24*a(n-25) -38*a(n-26) +8*a(n-27) -a(n-28) -a(n-30) +a(n-31)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207692 A207927 A208107 * A207598 A208117 A207702

Adjacent sequences:  A207725 A207726 A207727 * A207729 A207730 A207731

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 19 2012

STATUS

approved

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Last modified October 27 10:47 EDT 2021. Contains 348274 sequences. (Running on oeis4.)