A263702 Number of length n arrays of permutations of 0..n-1 with each element moved by -7 to 7 places and every three consecutive elements having its maximum within 4 of its minimum.
1, 2, 6, 24, 120, 288, 456, 768, 1002, 1759, 3766, 7984, 15880, 30712, 60880, 122308, 248493, 504104, 1014076, 2036337, 4085860, 8213550, 16539563, 33298322, 67024922, 134834240, 271198708, 545583481, 1097665701, 2208646386, 4443964256
Offset: 1
Keywords
Examples
Some solutions for n=7 ..0....2....4....1....0....6....2....0....0....5....1....6....3....0....3....6 ..1....6....1....0....1....2....6....4....4....2....4....4....6....4....6....2 ..2....5....0....4....3....3....5....3....3....1....5....5....2....1....4....5 ..3....3....2....2....2....5....4....6....1....0....6....3....5....5....5....3 ..5....1....3....5....4....1....3....2....2....3....2....1....1....3....1....4 ..4....4....5....3....6....4....0....5....5....4....3....2....4....2....2....1 ..6....0....6....6....5....0....1....1....6....6....0....0....0....6....0....0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A263703.
Formula
Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-5) +2*a(n-6) +a(n-7) +5*a(n-8) -4*a(n-9) -3*a(n-10) -3*a(n-11) -4*a(n-12) -4*a(n-14) -a(n-15) +3*a(n-16) -a(n-17) +a(n-19) for n>33
Comments