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A296400 Number of nX3 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 2 or 3 neighboring 1s. 1
1, 8, 24, 82, 316, 1182, 4560, 17508, 67310, 259398, 999368, 3851828, 14846772, 57226834, 220589358, 850295818, 3277615080, 12634174925, 48700783032, 187726368115, 723626846696, 2789356995974, 10752106442068, 41446037382414 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A296405.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -6*a(n-2) +8*a(n-3) -10*a(n-4) +22*a(n-5) -50*a(n-6) +37*a(n-7) -59*a(n-8) -3*a(n-10) -50*a(n-11) +10*a(n-12) -36*a(n-13) -17*a(n-14) -7*a(n-15) -19*a(n-16) -7*a(n-17) -4*a(n-18) -4*a(n-19) -a(n-20)

EXAMPLE

Some solutions for n=7

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

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

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

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

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

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

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

CROSSREFS

Cf. A296405.

Sequence in context: A141317 A146534 A180888 * A297808 A097544 A128688

Adjacent sequences:  A296397 A296398 A296399 * A296401 A296402 A296403

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 11 2017

STATUS

approved

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Last modified August 25 16:17 EDT 2019. Contains 326324 sequences. (Running on oeis4.)