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A316244
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 4, 5 or 8 king-move adjacent elements, with upper left element zero.
5
1, 1, 1, 1, 4, 1, 1, 8, 8, 1, 1, 24, 23, 24, 1, 1, 82, 103, 103, 82, 1, 1, 272, 520, 835, 520, 272, 1, 1, 908, 2671, 7017, 7017, 2671, 908, 1, 1, 3076, 13876, 60245, 99193, 60245, 13876, 3076, 1, 1, 10444, 72399, 522349, 1402577, 1402577, 522349, 72399, 10444, 1
OFFSET
1,5
COMMENTS
Table starts
.1.....1......1........1..........1............1..............1
.1.....4......8.......24.........82..........272............908
.1.....8.....23......103........520.........2671..........13876
.1....24....103......835.......7017........60245.........522349
.1....82....520.....7017......99193......1402577.......20134728
.1...272...2671....60245....1402577.....32646098......772981023
.1...908..13876...522349...20134728....772981023....30308496367
.1..3076..72399..4542604..288724218..18258025708..1182294908774
.1.10444.378321.39567170.4148322120.432527550123.46316454084857
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 4*a(n-1) -2*a(n-2) +2*a(n-3) -6*a(n-4) -4*a(n-5) for n>6
k=3: [order 15] for n>17
k=4: [order 47] for n>48
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..0. .0..1..0..1. .0..0..1..0. .0..1..0..0. .0..1..0..1
..0..1..1..0. .1..1..1..0. .1..1..1..1. .1..1..1..1. .1..1..1..0
..0..0..0..0. .0..0..1..0. .0..1..0..0. .1..0..0..0. .0..0..0..0
..1..0..0..1. .0..0..1..1. .1..0..0..1. .0..0..0..0. .1..1..0..1
..1..0..0..1. .1..1..1..0. .0..1..0..1. .1..0..1..1. .1..1..0..1
CROSSREFS
Column 2 is A303882.
Column 3 is A304414.
Column 4 is A304415.
Sequence in context: A306136 A317271 A304419 * A305954 A317215 A305685
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jun 27 2018
STATUS
approved