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A305360
T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 5 or 8 king-move adjacent elements, with upper left element zero.
5
1, 1, 1, 1, 4, 1, 1, 7, 7, 1, 1, 13, 13, 13, 1, 1, 26, 21, 21, 26, 1, 1, 49, 27, 26, 27, 49, 1, 1, 99, 53, 64, 64, 53, 99, 1, 1, 194, 99, 115, 137, 115, 99, 194, 1, 1, 387, 197, 211, 271, 271, 211, 197, 387, 1, 1, 773, 371, 439, 656, 538, 656, 439, 371, 773, 1, 1, 1538, 713, 870
OFFSET
1,5
COMMENTS
Table starts
.1...1...1...1....1....1.....1.....1......1.......1.......1........1........1
.1...4...7..13...26...49....99...194....387.....773....1538.....3081.....6147
.1...7..13..21...27...53....99...197....371.....713....1365.....2645.....5105
.1..13..21..26...64..115...211...439....870....1725....3513.....7141....14372
.1..26..27..64..137..271...656..1414...3251....7823...17334....40796....93604
.1..49..53.115..271..538..1476..3001...8018...19631...49142...121150...301994
.1..99..99.211..656.1476..4429.11281..31062...84750..233266...652271..1795948
.1.194.197.439.1414.3001.11281.33136..96562..302341..927289..2823816..8720038
.1.387.371.870.3251.8018.31062.96562.321576.1100993.3656995.12269156.41412932
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = a(n-1) +3*a(n-2) -4*a(n-4) for n>5
k=3: [order 16] for n>17
k=4: [order 67] for n>70
EXAMPLE
Some solutions for n=5 k=4
..0..0..1..1. .0..1..1..0. .0..1..1..0. .0..0..1..1. .0..0..0..0
..0..0..1..1. .1..0..1..0. .1..0..1..1. .1..1..0..0. .1..1..1..1
..1..1..1..1. .1..0..0..1. .0..1..0..1. .1..1..1..0. .1..0..0..1
..1..1..0..0. .1..0..1..0. .0..1..0..0. .0..0..1..0. .0..0..1..0
..1..1..0..0. .0..1..1..0. .1..0..1..1. .1..0..0..1. .1..1..1..0
CROSSREFS
Column 2 is A304004.
Column 3 is A304005.
Column 4 is A304006.
Sequence in context: A305047 A316733 A304010 * A304952 A316620 A304676
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 31 2018
STATUS
approved