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A247997 Number of length 2+5 0..n arrays with no disjoint triples in any consecutive six terms having the same sum 1
32, 702, 5316, 27800, 104620, 329742, 884032, 2131356, 4664480, 9508130, 18168932, 33008212, 57264516, 95672090, 154419880, 242095992, 369529512, 551174206, 804749300, 1153181480, 1623975972, 2251830342, 3077638456, 4151941100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A247995

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..45

FORMULA

Empirical: a(n) = 2*a(n-1) +2*a(n-2) -4*a(n-3) -3*a(n-4) +7*a(n-6) +4*a(n-7) -5*a(n-8) -4*a(n-9) -5*a(n-10) +4*a(n-11) +7*a(n-12) -3*a(n-14) -4*a(n-15) +2*a(n-16) +2*a(n-17) -a(n-18)

Empirical for n mod 12 = 0: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (641/6)*n

Empirical for n mod 12 = 1: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (24079/96)*n + (111235/288)

Empirical for n mod 12 = 2: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (107/2)*n + (2260/9)

Empirical for n mod 12 = 3: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (24079/96)*n + (16555/32)

Empirical for n mod 12 = 4: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (641/6)*n - (640/9)

Empirical for n mod 12 = 5: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (9733/32)*n + (209795/288)

Empirical for n mod 12 = 6: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (641/6)*n - 20

Empirical for n mod 12 = 7: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (24079/96)*n + (128515/288)

Empirical for n mod 12 = 8: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (107/2)*n + (2440/9)

Empirical for n mod 12 = 9: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (24079/96)*n + (14635/32)

Empirical for n mod 12 = 10: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (4180/9)*n^3 - (12625/24)*n^2 + (641/6)*n - (820/9)

Empirical for n mod 12 = 11: a(n) = n^7 - 4*n^6 + (1523/32)*n^5 - (5325/32)*n^4 + (64225/144)*n^3 - (20525/48)*n^2 - (9733/32)*n + (227075/288)

EXAMPLE

Some solutions for n=5

..4....0....4....5....2....5....5....2....3....2....1....3....1....3....3....2

..1....5....5....4....0....1....3....2....2....0....1....4....2....1....5....3

..1....4....5....2....1....4....0....4....1....0....4....3....0....5....5....2

..5....0....0....1....5....2....0....3....3....1....5....5....3....3....2....3

..2....3....5....5....1....0....3....1....1....1....0....3....2....4....4....0

..4....5....3....0....2....3....4....1....3....1....0....5....5....1....2....1

..2....0....0....3....4....5....3....2....3....2....4....1....0....1....3....0

CROSSREFS

Sequence in context: A025031 A025008 A020984 * A199708 A264093 A062261

Adjacent sequences:  A247994 A247995 A247996 * A247998 A247999 A248000

KEYWORD

nonn

AUTHOR

R. H. Hardin, Sep 28 2014

STATUS

approved

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Last modified January 25 14:42 EST 2021. Contains 340416 sequences. (Running on oeis4.)