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A297871
Number of nX3 0..1 arrays with every element equal to 2, 3 or 5 king-move adjacent elements, with upper left element zero.
2
0, 3, 0, 3, 0, 3, 6, 23, 68, 205, 572, 1553, 4208, 11405, 30988, 84553, 231176, 632915, 1734004, 4751591, 13021550, 35685855, 97797264, 268015939, 734511376, 2012982445, 5516772882, 15119337301, 41436399090, 113561805901, 311231201784
OFFSET
1,2
COMMENTS
Column 3 of A297876.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +5*a(n-2) -3*a(n-3) -15*a(n-4) -9*a(n-5) +24*a(n-6) +29*a(n-7) -a(n-8) -36*a(n-9) -67*a(n-10) -23*a(n-11) +49*a(n-12) +43*a(n-13) +14*a(n-14) +3*a(n-15) -4*a(n-16) -2*a(n-17) for n>18
EXAMPLE
All solutions for n=7
..0..0..1. .0..0..1. .0..0..0. .0..1..1. .0..1..1. .0..0..0
..0..1..1. .0..1..1. .1..0..1. .0..0..1. .0..0..1. .1..0..1
..0..1..0. .0..1..0. .1..1..1. .1..0..1. .1..0..1. .1..1..1
..1..0..0. .1..0..0. .1..0..0. .1..1..0. .1..1..0. .0..0..1
..0..1..0. .1..1..1. .0..1..0. .0..0..0. .1..0..1. .0..1..0
..0..1..1. .1..0..1. .0..1..1. .0..1..0. .0..0..1. .1..1..0
..0..0..1. .0..0..0. .0..0..1. .1..1..1. .0..1..1. .1..0..0
CROSSREFS
Cf. A297876.
Sequence in context: A221168 A194084 A262281 * A292130 A291971 A240923
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 07 2018
STATUS
approved