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A248536
Number of length n+3 0..7 arrays with every four consecutive terms having the sum of some three elements equal to three times the fourth
1
512, 704, 992, 1412, 2000, 2960, 4424, 6644, 9968, 15356, 23648, 36380, 55856, 87680, 137072, 213500, 331424, 525044, 827144, 1296776, 2024480, 3222092, 5096048, 8016536, 12551888, 20024372, 31734104, 50006852, 78415616, 125248544
OFFSET
1,1
COMMENTS
Column 7 of A248537
LINKS
FORMULA
Empirical: a(n) = a(n-1) +12*a(n-4) -12*a(n-5) -47*a(n-8) +47*a(n-9) +81*a(n-12) -81*a(n-13) -76*a(n-16) +76*a(n-17) +36*a(n-20) -36*a(n-21) -8*a(n-24) +8*a(n-25)
EXAMPLE
Some solutions for n=6
..4....0....0....4....1....7....2....5....2....3....3....7....3....1....4....6
..4....3....3....5....2....0....0....3....6....5....6....0....1....3....7....3
..5....3....5....3....0....5....2....4....4....4....5....4....4....5....3....3
..3....6....4....4....5....4....4....4....4....4....6....5....4....3....2....4
..0....4....4....4....1....3....2....1....2....3....7....3....7....1....4....2
..4....3....7....1....2....4....0....3....6....5....6....4....5....3....3....3
..5....3....5....7....0....5....2....4....4....4....5....4....0....5....3....3
..3....6....0....4....1....0....4....4....4....0....2....1....4....3....6....0
..0....4....4....4....5....7....2....5....2....7....7....7....7....1....4....6
CROSSREFS
Sequence in context: A326113 A045003 A234136 * A202461 A046311 A036333
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 08 2014
STATUS
approved