A189500 Number of arrangements of 4 nonzero numbers x(i) in -n..n with the sum of floor(x(i)/x(i+1)) equal to zero

0, 42, 152, 462, 1088, 2128, 3850, 6474, 10126, 15224, 22180, 30900, 42164, 56514, 73816, 94984, 120700, 150836, 186756, 228696, 276618, 332204, 396444, 467948, 549504, 642000, 744978, 859846, 988550, 1129542, 1286278, 1458874, 1646896

Offset

1,2

Comments

Row 3 of A189498

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Example

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

Crossrefs

Sequence in context: A299131 A158479 A188126 * A350579 A075289 A193571

Adjacent sequences: A189497 A189498 A189499 * A189501 A189502 A189503

Keyword

nonn

Author

R. H. Hardin Apr 23 2011

Status

approved