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A317604
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
7
1, 2, 2, 4, 8, 4, 8, 23, 23, 8, 16, 65, 100, 65, 16, 32, 192, 435, 435, 192, 32, 64, 569, 1959, 3047, 1959, 569, 64, 128, 1709, 8872, 20805, 20805, 8872, 1709, 128, 256, 5162, 40080, 143866, 218043, 143866, 40080, 5162, 256, 512, 15663, 181116, 994993, 2349106
OFFSET
1,2
COMMENTS
Table starts
...1.....2......4........8.........16...........32.............64
...2.....8.....23.......65........192..........569...........1709
...4....23....100......435.......1959.........8872..........40080
...8....65....435.....3047......20805.......143866.........994993
..16...192...1959....20805.....218043......2349106.......25248997
..32...569...8872...143866....2349106.....40015089......679103465
..64..1709..40080...994993...25248997....679103465....18167894481
.128..5162.181116..6892556..271168201..11512061359...485582717996
.256.15663.818827.47747495.2915768974.195586936443.13027760526423
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 3*a(n-1) +3*a(n-2) -6*a(n-3) -8*a(n-4) for n>5
k=3: [order 16] for n>17
k=4: [order 57] for n>59
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..0. .0..1..0..0. .0..0..1..0. .0..0..0..1. .0..0..1..0
..0..0..0..0. .1..1..1..0. .0..1..1..0. .0..1..0..0. .0..1..1..1
..1..0..0..0. .1..0..1..0. .0..0..0..1. .1..1..1..1. .1..1..1..1
..0..0..1..1. .0..0..0..1. .0..0..1..1. .1..0..1..1. .0..1..0..1
..0..0..0..1. .1..0..0..1. .1..1..0..0. .0..1..0..0. .1..1..1..1
CROSSREFS
Column 1 is A000079(n-1).
Column 2 is A304304.
Sequence in context: A305593 A317011 A316876 * A038208 A240484 A240636
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Aug 01 2018
STATUS
approved