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A302885
Number of nX4 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
1, 20, 53, 238, 1102, 5570, 28594, 149206, 788373, 4194079, 22418762, 120168046, 645271922, 3468733058, 18659308842, 100416125479, 540536282078, 2910157350115, 15669370152621, 84374942124034, 454351598306349
OFFSET
1,2
COMMENTS
Column 4 of A302889.
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) -6*a(n-2) -5*a(n-3) -32*a(n-4) -130*a(n-5) +86*a(n-6) +185*a(n-7) +394*a(n-8) +1235*a(n-9) -26*a(n-10) -384*a(n-11) -751*a(n-12) -6365*a(n-13) -1429*a(n-14) -3066*a(n-15) -469*a(n-16) +4458*a(n-17) +2506*a(n-18) +1808*a(n-19) +2590*a(n-20) +761*a(n-21) -73*a(n-22) +453*a(n-23) -497*a(n-24) -885*a(n-25) -107*a(n-26) +36*a(n-27) -329*a(n-28) -40*a(n-29) +74*a(n-30) -28*a(n-31) -22*a(n-32) +28*a(n-33) +20*a(n-34) +4*a(n-35) for n>37
EXAMPLE
Some solutions for n=5
..0..1..1..0. .0..0..0..0. .0..0..1..1. .0..1..1..1. .0..0..0..1
..1..1..1..1. .1..0..0..0. .0..0..1..1. .1..1..1..0. .1..0..0..0
..1..1..1..0. .1..0..0..1. .1..1..1..1. .0..0..1..1. .1..0..1..1
..0..1..1..1. .0..0..0..1. .0..1..1..0. .1..0..0..0. .0..0..1..1
..0..1..1..0. .1..0..0..1. .1..1..1..0. .1..0..0..0. .0..0..1..1
CROSSREFS
Cf. A302889.
Sequence in context: A188250 A329627 A329628 * A059677 A301372 A108108
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 15 2018
STATUS
approved