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A233869
Number of (n+1)X(1+1) 0..7 arrays with every 2X2 subblock having the sum of the absolute values of all six edge and diagonal differences equal to 21
1
224, 1176, 5984, 34416, 189632, 1128928, 6414208, 38622656, 222041856, 1341849472, 7749914112, 46887986944, 271306185728, 1642034355712, 9508544919552, 57555613998080, 333396836184064, 2018143397804032
OFFSET
1,1
COMMENTS
Column 1 of A233875
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +72*a(n-2) -136*a(n-3) -1764*a(n-4) +2984*a(n-5) +18928*a(n-6) -25920*a(n-7) -92800*a(n-8) +81920*a(n-9) +204800*a(n-10) -81920*a(n-11) -172032*a(n-12) +16384*a(n-13) +32768*a(n-14)
EXAMPLE
Some solutions for n=5
..0..6....0..1....0..6....6..6....6..3....0..7....2..5....6..0....0..7....4..1
..6..7....1..7....3..0....0..3....0..6....3..3....7..1....4..1....1..1....7..1
..0..6....6..3....6..0....3..7....5..2....7..0....6..3....7..7....0..7....2..5
..3..0....6..0....3..6....3..0....6..0....7..7....1..7....4..1....6..6....7..1
..6..0....0..3....0..6....0..6....6..7....7..0....2..5....6..0....7..0....0..1
..1..4....6..6....7..6....3..6....6..0....2..2....1..7....3..0....4..4....7..1
CROSSREFS
Sequence in context: A061524 A156813 A233875 * A146745 A015048 A229589
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2013
STATUS
approved