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A297803 Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2, 3 or 5 neighboring 1s. 1
1, 4, 37, 100, 293, 1320, 6215, 24879, 99567, 422308, 1804127, 7556513, 31570236, 132859288, 559967531, 2354250563, 9891690637, 41598759825, 174990998789, 735895232858, 3094315102349, 13012504569964, 54724162019621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 3 of A297802.

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) +19*a(n-3) +32*a(n-4) -91*a(n-5) -260*a(n-7) -403*a(n-8) +590*a(n-9) +467*a(n-10) +69*a(n-11) -380*a(n-12) -48*a(n-13) -115*a(n-14) +216*a(n-15) +359*a(n-16) +36*a(n-17) -221*a(n-18) -89*a(n-19) -5*a(n-20) +12*a(n-21)

EXAMPLE

Some solutions for n=7

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

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

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

CROSSREFS

Cf. A297802.

Sequence in context: A103369 A031189 A045555 * A183378 A145401 A297745

Adjacent sequences:  A297800 A297801 A297802 * A297804 A297805 A297806

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 06 2018

STATUS

approved

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Last modified July 30 23:12 EDT 2021. Contains 346365 sequences. (Running on oeis4.)