A188357
Number of arrangements of n+1 numbers x(i) in -8..8 with the sum of x(i)*x(i+1) equal to zero.
Original entry on oeis.org
33, 561, 2161, 34625, 283893, 4409889, 55520361, 870473329, 12869671489, 204942934341, 3212586862645
Offset: 1
Some solutions for n=4
.-7....6...-2...-3....4...-7...-5....0....0....0...-4...-7....8....1...-5....3
.-1....5....0....8....3....0....0...-6....0...-4...-2...-7...-6...-8....0....3
..7...-6...-7....3....0...-3...-6...-4...-3....3....4....5....0....1...-7...-5
.-2....4...-5...-7....4....0....4....3...-7...-4....0...-7....6...-8....5...-3
.-7....6....7...-3...-3...-2....6...-4....3...-6...-3...-3....8...-3....7....3
A188361
Number of arrangements of 6 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero.
Original entry on oeis.org
197, 1953, 7369, 22229, 45801, 100885, 163745, 283893, 438373, 678617, 911709, 1386673, 1772141, 2399001, 3175561, 4167365, 5010369, 6549541, 7719713, 9789981, 11867065, 14232893, 16279425, 20224801
Offset: 1
Some solutions for n=4
..0...-2...-2....4....2...-3...-2....3...-4....1....1...-4....4....2....2....3
.-3...-1...-3...-2....0...-2...-3...-1....2....0...-1....1....1....3....0....3
.-3....0....2....2...-2...-3....3....1...-1...-3....1...-1....4...-1....0...-3
..2...-3....2....4...-3....4....4....4...-1....3....0...-3...-2....1...-1....2
.-1....1...-2....4....2....4...-3....0....3....3...-1....2...-4...-1....0....2
..1....1....0...-3....0...-4...-1....2....4....0...-2....4....2....1....0....1
A188362
Number of arrangements of 7 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero.
Original entry on oeis.org
627, 9153, 49747, 181449, 480363, 1171345, 2295051, 4409889, 7651651, 12818961, 19584123, 30982585, 44149827, 63627969, 89493523, 123568713
Offset: 1
Some solutions for n=4
..0....4....0...-1....0....1...-1...-1....0....2....3....0....1...-1....1...-3
..0...-1....0....0....0...-1...-1...-2...-2....0...-2...-3...-2...-1...-2...-4
.-2....4....0...-1....3...-1....1....1....0...-2....1....2....1...-2...-2....4
.-3...-1....4...-3....1....0....3...-4....4....1....0....1....4....1....3....0
..2....0....0....1...-3....3...-1...-1....1....0....1....0...-2...-1....2...-1
..0....3....0....2....0....0....0....1....2...-2....2...-1...-2....0....2....2
..4....4...-2...-1....3....4...-3....1...-3...-1....3...-4...-2...-3...-3....3
A188363
Number of arrangements of 8 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero.
Original entry on oeis.org
1477, 37269, 262925, 1264985, 3882729, 11535493, 25217201, 55520361, 106276821, 198605017, 325986813, 569829701, 864406561
Offset: 1
Some solutions for n=4
.-4...-4...-2...-4...-2...-1...-2...-3...-2...-1...-3...-4...-1...-4...-3...-3
.-4...-3...-3...-3...-4...-4...-3...-3...-3...-4...-4...-4...-3...-3...-4...-4
..2....4....0....3....3....4...-4....0....0...-2....0....4...-2....0...-1....1
.-2....2....3...-1....2....1....4....3....2....0....2...-3....4...-1....4....4
..4....4....2...-3...-2....0....0...-3....3...-3....3...-4...-3....3....0....2
..1...-4....4....1...-1...-1....2....0....0...-4...-2....0...-1...-1...-1...-2
..0...-3...-4....0....0...-4....1....0....3....3....2....0...-4...-2...-4....4
..4....4....1....3...-2...-1...-4...-4...-4...-4...-4...-2...-1....4....4...-2
A188364
Number of arrangements of 9 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero.
Original entry on oeis.org
4671, 173409, 1763151, 10396729, 40629247, 136061137, 355442823, 870473329, 1876439327, 3821007601, 7047842559
Offset: 1
Some solutions for n=4
.-4...-3...-3...-3...-4...-3...-4...-4...-3...-3...-4...-4...-3...-4...-3...-3
.-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4...-4
..0....0....1....1...-4....0....2...-1....0...-4...-1....2....1....1....1....1
.-1...-4...-1...-4...-3...-1...-2....3....3....4....4...-2....1....1...-1....1
..3...-3...-1....2....4....4...-1...-4...-4...-2...-3....2...-3...-3...-2...-3
.-2....2....2....4...-4...-4...-2....1...-1....2....0...-2....4...-2....1....4
..2...-3...-4....0....4...-3....2....3....1...-1...-1....0....0...-4....2....0
.-3....4...-1....2....2....4...-4....4...-3....2....2....1....2....3...-3....3
.-1....0....2...-2...-4....2...-1...-4....0....2...-1....4....3...-4....1....2
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