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A304763
Number of nX4 0..1 arrays with every element unequal to 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.
2
0, 18, 103, 1321, 14831, 172574, 1999511, 23203301, 269239457, 3124340783, 36256268039, 420735862555, 4882434935230, 56658308917014, 657492489276366, 7629885182274593, 88541161447587510, 1027477755118952667
OFFSET
1,2
COMMENTS
Column 4 of A304767.
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) +32*a(n-2) +28*a(n-3) -438*a(n-4) -1381*a(n-5) -1262*a(n-6) +2558*a(n-7) +11422*a(n-8) +10902*a(n-9) -6871*a(n-10) -32728*a(n-11) -20247*a(n-12) +32404*a(n-13) +39356*a(n-14) -24471*a(n-15) -54052*a(n-16) -1137*a(n-17) +38628*a(n-18) +11519*a(n-19) -11656*a(n-20) +7783*a(n-21) +16422*a(n-22) +130*a(n-23) -5306*a(n-24) +225*a(n-25) -432*a(n-26) -1544*a(n-27) +54*a(n-28) +384*a(n-29) +24*a(n-30) -32*a(n-31) for n>32
EXAMPLE
Some solutions for n=5
..0..1..0..1. .0..1..0..0. .0..0..1..0. .0..1..1..0. .0..1..0..1
..0..1..0..1. .0..1..1..1. .1..1..0..1. .1..1..0..1. .1..1..1..0
..1..1..0..0. .0..0..0..0. .0..1..1..0. .1..0..1..0. .0..1..0..0
..0..1..0..1. .1..1..0..1. .1..0..0..1. .0..1..0..0. .0..0..0..1
..1..0..0..1. .0..1..0..1. .1..0..0..1. .0..1..0..1. .1..1..0..1
CROSSREFS
Cf. A304767.
Sequence in context: A285043 A223241 A197339 * A322648 A285854 A123277
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 18 2018
STATUS
approved