A247406 Number of length 2+4 0..n arrays with no disjoint pairs in any consecutive five terms having the same sum

0, 40, 264, 1544, 6216, 19080, 49032, 113896, 237456, 466640, 856512, 1494696, 2491584, 4009888, 6231576, 9423824, 13882728, 20009088, 28250184, 39194656, 53468496, 71900744, 95363904, 124954128, 161852112, 207511288, 263443896

Offset

1,2

Comments

Row 2 of A247404

Links

R. H. Hardin, Table of n, a(n) for n = 1..95

Formula

Empirical: a(n) = a(n-1) +a(n-3) +a(n-4) -a(n-5) -2*a(n-7) -a(n-8) -a(n-9) +a(n-11) +3*a(n-12) +a(n-13) +2*a(n-14) -2*a(n-16) -a(n-17) -3*a(n-18) -a(n-19) +a(n-21) +a(n-22) +2*a(n-23) +a(n-25) -a(n-26) -a(n-27) -a(n-29) +a(n-30)

Example

Some solutions for n=6
..5....5....0....6....1....2....5....4....4....3....0....0....6....0....5....0
..4....3....6....5....6....6....6....5....3....5....5....6....6....1....4....6
..2....0....2....2....3....6....5....4....3....5....5....3....3....5....0....4
..2....3....6....0....3....0....2....6....0....5....5....2....6....2....4....1
..6....3....6....0....2....3....0....1....5....0....3....2....1....0....4....4
..2....2....5....1....3....6....0....6....3....2....6....4....6....5....5....0

Crossrefs

Sequence in context: A223426 A290127 A115170 * A229588 A334121 A117216

Adjacent sequences: A247403 A247404 A247405 * A247407 A247408 A247409

Keyword

nonn

Author

R. H. Hardin, Sep 16 2014

Status

approved