A248450 Number of length 2+5 0..n arrays with no three disjoint pairs in any consecutive six terms having the same sum

62, 1272, 11436, 59480, 226410, 694632, 1824272, 4257336, 9061830, 17909120, 33303852, 58859112, 99630266, 162505920, 256670520, 394127072, 590308422, 864758736, 1241905340, 1751918880, 2431676802, 3325811912, 4487885496

Offset

1,1

Comments

Row 2 of A248448

Links

R. H. Hardin, Table of n, a(n) for n = 1..54

Formula

Empirical: a(n) = 4*a(n-1) -5*a(n-2) +2*a(n-3) -2*a(n-4) +2*a(n-5) +5*a(n-6) -8*a(n-7) +6*a(n-8) -8*a(n-9) +5*a(n-10) +2*a(n-11) -2*a(n-12) +2*a(n-13) -5*a(n-14) +4*a(n-15) -a(n-16)

Empirical for n mod 12 = 0: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 74*n

Empirical for n mod 12 = 1: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 89*n + (235/18)

Empirical for n mod 12 = 2: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + (142/3)*n + (1000/9)

Empirical for n mod 12 = 3: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 89*n + (195/2)

Empirical for n mod 12 = 4: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 74*n + (320/9)

Empirical for n mod 12 = 5: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + (187/3)*n + (1595/18)

Empirical for n mod 12 = 6: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 74*n

Empirical for n mod 12 = 7: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 89*n + (2395/18)

Empirical for n mod 12 = 8: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + (142/3)*n + (1000/9)

Empirical for n mod 12 = 9: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 89*n - (45/2)

Empirical for n mod 12 = 10: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + 74*n + (320/9)

Empirical for n mod 12 = 11: a(n) = n^7 + 7*n^6 + 6*n^5 + (55/2)*n^4 + (415/9)*n^3 - (383/3)*n^2 + (187/3)*n + (3755/18)

Example

Some solutions for n=4
..3....0....3....1....3....0....1....2....2....1....4....3....3....1....3....2
..0....1....0....4....4....1....0....1....1....2....2....1....0....2....4....4
..2....4....1....4....0....1....2....1....0....1....2....0....1....0....0....0
..2....0....3....3....3....3....3....3....3....0....3....3....0....3....4....3
..3....2....4....3....4....3....1....0....0....3....0....0....2....1....1....4
..1....1....2....0....3....3....4....0....1....3....3....0....0....0....3....0
..0....4....3....3....4....4....3....3....0....3....1....0....0....1....3....2

Crossrefs

Sequence in context: A250564 A231027 A103428 * A115504 A296359 A037962

Adjacent sequences: A248447 A248448 A248449 * A248451 A248452 A248453

Keyword

nonn

Author

R. H. Hardin, Oct 06 2014

Status

approved