A247529 Number of length n+3 0..4 arrays with some disjoint pairs in every consecutive four terms having the same sum

185, 317, 561, 1007, 1823, 3455, 6495, 12105, 22459, 43255, 82157, 154279, 287847, 556213, 1059205, 1992823, 3723991, 7202379, 13726813, 25838725, 48308217, 93456427, 178172281, 335410643, 627185919, 1213463869, 2313820457, 4355601755

Offset

1,1

Comments

Column 4 of A247533

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = a(n-1) +4*a(n-2) -4*a(n-3) +18*a(n-4) -18*a(n-5) -78*a(n-6) +78*a(n-7) -67*a(n-8) +67*a(n-9) +386*a(n-10) -386*a(n-11) +22*a(n-12) -22*a(n-13) -686*a(n-14) +686*a(n-15) +125*a(n-16) -125*a(n-17) +616*a(n-18) -616*a(n-19) -178*a(n-20) +178*a(n-21) -340*a(n-22) +340*a(n-23) +130*a(n-24) -130*a(n-25) +80*a(n-26) -80*a(n-27) -40*a(n-28) +40*a(n-29) for n>30

Example

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

Crossrefs

Sequence in context: A244248 A129311 A252272 * A301991 A136048 A209373

Adjacent sequences: A247526 A247527 A247528 * A247530 A247531 A247532

Keyword

nonn

Author

R. H. Hardin, Sep 18 2014

Status

approved