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A262319
T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each row and column divisible by 7, read as a binary number with top and left being the most significant bits.
6
2, 3, 3, 5, 5, 5, 10, 9, 9, 10, 19, 27, 17, 27, 19, 37, 61, 133, 133, 61, 37, 74, 145, 361, 1618, 361, 145, 74, 147, 435, 1009, 6043, 6043, 1009, 435, 147, 293, 1253, 8357, 42661, 37873, 42661, 8357, 1253, 293, 586, 3593, 33993, 683218, 413893, 413893, 683218
OFFSET
1,1
COMMENTS
Table starts
...2.....3......5.......10........19........37........74........147........293
...3.....5......9.......27........61.......145.......435.......1253.......3593
...5.....9.....17......133.......361......1009......8357......33993.....127121
..10....27....133.....1618......6043.....42661....683218....4276587...39384421
..19....61....361.....6043.....37873....413893...8003035..103003837.1659181705
..37...145...1009....42661....413893...7914829.281951533.7901300449
..74...435...8357...683218...8003035.281951533
.147..1253..33993..4276587.103003837
.293..3593.127121.39384421
.586.10779.795013
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4)
k=2: [order 15]
k=3: [order 43]
k=4: [order 29]
EXAMPLE
Some solutions for n=4 k=4
..0..1..0..1..0..1....1..0..0..0..1..1....0..1..0..1..0..1....0..0..0..1..1..1
..1..0..1..0..1..0....1..0..0..0..1..1....1..1..1..1..1..1....0..0..0..1..1..1
..1..1..1..1..1..1....0..0..0..1..1..1....1..1..1..1..1..1....0..0..0..0..0..0
..1..0..1..0..1..0....0..0..1..1..1..0....1..1..1..1..1..1....1..1..1..0..0..0
..0..1..0..1..0..1....0..0..1..1..1..0....0..1..0..1..0..1....1..1..1..0..0..0
..0..0..0..0..0..0....1..0..1..0..1..0....0..1..0..1..0..1....1..1..1..1..1..1
CROSSREFS
Column 1 is A046630.
Sequence in context: A087172 A262457 A286870 * A262488 A278530 A330332
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Sep 17 2015
STATUS
approved