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A246485
Number of length 6+3 0..n arrays with no pair in any consecutive four terms totalling exactly n
1
2, 52, 3132, 31104, 347934, 1893780, 9714968, 35251360, 119069850, 331355220, 869135892, 2019732192, 4480392182, 9156814324, 18041010864, 33514806720, 60460359858, 104364198900, 175893704300, 286474229440, 457427541582
OFFSET
1,1
COMMENTS
Row 6 of A246479
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +4*a(n-2) -20*a(n-3) +56*a(n-5) -28*a(n-6) -84*a(n-7) +70*a(n-8) +70*a(n-9) -84*a(n-10) -28*a(n-11) +56*a(n-12) -20*a(n-14) +4*a(n-15) +3*a(n-16) -a(n-17)
EXAMPLE
Some solutions for n=4
..2....3....0....1....4....1....1....0....4....4....1....3....2....4....2....0
..3....4....3....1....3....1....0....0....4....4....1....0....0....4....4....2
..3....2....3....1....3....4....1....1....3....4....4....2....0....2....3....1
..3....3....2....2....3....2....1....1....3....3....1....3....3....3....4....1
..2....4....4....4....3....4....1....1....2....3....1....3....3....4....3....1
..0....3....3....1....3....4....1....1....3....2....1....3....3....4....4....1
..0....2....3....4....4....4....4....2....4....4....1....3....3....4....4....2
..1....3....2....1....3....4....1....4....4....4....1....2....3....3....4....1
..0....3....0....2....4....2....1....4....2....4....4....3....4....4....3....4
CROSSREFS
Sequence in context: A215744 A099882 A216611 * A340837 A121293 A246743
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 27 2014
STATUS
approved