A190832 Number of permutations of 4 copies of 1..n introduced in order 1..n with no element equal to another within a distance of 3.

0, 0, 0, 1, 9993, 44288275, 216956034178, 1368009041285362

Offset

1,5

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A182696 A126978 A188790 * A043528 A089521 A084474

Adjacent sequences: A190829 A190830 A190831 * A190833 A190834 A190835

Keyword

nonn,more

Author

R. H. Hardin, May 21 2011

Status

approved