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A302666 Number of nX4 0..1 arrays with every element equal to 1, 2, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
2, 45, 164, 934, 4267, 21949, 106793, 529984, 2617548, 12938179, 63986777, 316244862, 1563877465, 7731246308, 38227036552, 188999363652, 934471931880, 4620268994057, 22843909984025, 112946725741085, 558440468796391 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A302670.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) +12*a(n-2) -47*a(n-3) -101*a(n-4) +45*a(n-5) +381*a(n-6) +1292*a(n-7) +42*a(n-8) -5366*a(n-9) -7123*a(n-10) +6047*a(n-11) +22989*a(n-12) +15537*a(n-13) -22434*a(n-14) -51326*a(n-15) -29224*a(n-16) +38509*a(n-17) +82591*a(n-18) +44309*a(n-19) -44268*a(n-20) -87403*a(n-21) -42575*a(n-22) +28053*a(n-23) +52051*a(n-24) +24821*a(n-25) -7290*a(n-26) -13614*a(n-27) -6288*a(n-28) +190*a(n-29) +1280*a(n-30) +312*a(n-31) +20*a(n-32) for n>35

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A302670.

Sequence in context: A281661 A019579 A302220 * A304693 A200158 A316444

Adjacent sequences:  A302663 A302664 A302665 * A302667 A302668 A302669

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 11 2018

STATUS

approved

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Last modified July 25 16:03 EDT 2021. Contains 346291 sequences. (Running on oeis4.)