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A198649
Number of n X 2 0..6 arrays with values 0..6 introduced in row major order and each element equal to at least one horizontal or vertical neighbor.
1
1, 3, 14, 76, 488, 3521, 28030, 242849, 2264711, 22514016, 236355581, 2595953878, 29564752028, 346348460016, 4145325240330, 50411121219126, 620250713489362, 7696399884065815, 96085558605681094, 1204839099133770019
OFFSET
1,2
COMMENTS
Column 2 of A198654.
LINKS
FORMULA
Empirical: a(n)=37*a(n-1)-502*a(n-2)+2817*a(n-3)-2399*a(n-4)-35852*a(n-5)+95494*a(n-6)+127482*a(n-7)-450424*a(n-8)-527274*a(n-9)+944990*a(n-10)+1784424*a(n-11)-456873*a(n-12)-2779579*a(n-13)-1492318*a(n-14)+1457417*a(n-15)+1939617*a(n-16)+390628*a(n-17)-559484*a(n-18)-375300*a(n-19)-62900*a(n-20).
EXAMPLE
Some solutions with all values 0 to 6 for n=7
..0..0....0..0....0..1....0..0....0..0....0..0....0..0....0..1....0..1....0..1
..1..1....1..1....0..1....1..1....1..1....1..1....1..2....0..1....0..1....0..1
..2..2....2..2....2..3....2..2....2..3....2..2....1..2....2..2....2..2....2..2
..3..4....3..3....2..3....3..4....2..3....3..3....3..3....3..4....3..3....3..4
..3..4....4..4....4..4....3..4....4..4....4..5....4..4....3..4....4..4....3..4
..5..6....5..6....5..6....5..5....5..5....4..5....5..5....5..6....5..6....5..5
..5..6....5..6....5..6....6..6....6..6....6..6....6..6....5..6....5..6....6..6
CROSSREFS
Cf. A198654.
Sequence in context: A353253 A198702 A198621 * A198656 A240402 A048779
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 28 2011
STATUS
approved