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A245992
Number of length n+2 0..5 arrays with no pair in any consecutive three terms totalling exactly 5
1
126, 534, 2262, 9582, 40590, 171942, 728358, 3085374, 13069854, 55364790, 234529014, 993480846, 4208452398, 17827290438, 75517614150, 319897747038, 1355108602302, 5740332156246, 24316437227286, 103006081065390
OFFSET
1,1
COMMENTS
Column 5 of A245995
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +a(n-2).
Empirical: G.f.: -6*x*(21+5*x) / ( -1+4*x+x^2 ). - R. J. Mathar, Aug 10 2014
EXAMPLE
Some solutions for n=6
..3....1....0....1....3....0....0....3....1....1....4....3....1....0....1....4
..3....2....0....3....5....1....0....3....2....0....3....1....2....2....1....4
..0....1....0....1....5....0....2....4....2....3....5....3....1....1....3....2
..4....2....1....1....3....2....1....4....4....3....5....3....2....0....5....0
..4....5....1....5....1....0....2....2....0....0....2....0....0....1....5....1
..5....2....5....2....5....2....2....2....3....0....4....0....4....0....4....3
..5....1....2....5....2....1....4....0....3....0....2....2....2....3....4....1
..1....2....2....5....2....2....4....2....0....1....0....4....4....0....2....0
CROSSREFS
Sequence in context: A154039 A202601 A202594 * A267566 A165023 A186825
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 09 2014
STATUS
approved