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A189547
Number of arrangements of 4 nonzero numbers x(i) in -n..n with the sum of trunc(x(i)/x(i+1)) equal to zero.
1
0, 44, 192, 544, 1340, 2520, 4620, 7716, 12500, 18896, 27876, 38860, 53492, 71460, 93972, 121328, 155180, 194484, 241980, 296528, 360804, 434048, 519528, 614164, 723528, 845504, 983924, 1136840, 1309496, 1497332, 1707736, 1938160, 2193024
OFFSET
1,2
COMMENTS
Row 3 of A189545.
LINKS
EXAMPLE
Some solutions for n=5
..5...-1....5....1...-4...-1...-2...-3...-1....4....3....1....4....4...-1....1
.-2....2....3....1....3....4....5....2...-1...-3....2....1....3....4...-2...-2
.-1...-2....5....5...-5....3....2....5...-3...-4...-2...-1...-2...-4....3....2
.-5...-2...-4...-4...-4...-3...-1....4....3...-3...-4...-5...-3...-5....5....2
CROSSREFS
Cf. A189545.
Sequence in context: A006563 A159033 A238249 * A026908 A183246 A186248
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 23 2011
STATUS
approved