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A206983 Number of nX4 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal 1
10, 100, 158, 556, 1866, 5804, 18528, 59888, 191484, 612874, 1966402, 6301118, 20187672, 64705162, 207369486, 664535672, 2129687696, 6825166670, 21872797724, 70096742330, 224642588748, 719921959060, 2307166259316, 7393882758084 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A206987

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +10*a(n-3) -18*a(n-4) +8*a(n-5) -16*a(n-6) -4*a(n-7) -3*a(n-8) +21*a(n-9) +13*a(n-10) -12*a(n-11) for n>13

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A208381 A031187 A029797 * A207841 A072082 A078259

Adjacent sequences:  A206980 A206981 A206982 * A206984 A206985 A206986

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 14 2012

STATUS

approved

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Last modified January 24 07:13 EST 2021. Contains 340398 sequences. (Running on oeis4.)