A188358 - OEIS

%I #5 Mar 31 2012 12:36:12

%S 5,9,15,13,45,29,17,91,117,91,21,153,257,565,197,25,231,497,1775,1953,

%T 627,29,325,749,4201,7369,9153,1477,33,435,1205,8051,22229,49747,

%U 37269,4671,37,561,1569,14477,45801,181449,262925,173409,11693,41,703,2161

%N T(n,k)=Number of arrangements of n+1 numbers x(i) in -k..k with the sum of x(i)*x(i+1) equal to zero

%C Table starts

%C .....5.......9.......13........17.........21..........25..........29

%C ....15......45.......91.......153........231.........325.........435

%C ....29.....117......257.......497........749........1205........1569

%C ....91.....565.....1775......4201.......8051.......14477.......22583

%C ...197....1953.....7369.....22229......45801......100885......163745

%C ...627....9153....49747....181449.....480363.....1171345.....2295051

%C ..1477...37269...262925...1264985....3882729....11535493....25217201

%C ..4671..173409..1763151..10396729...40629247...136061137...355442823

%C .11693..766869.10536621..81850801..383541193..1540834589..4602176797

%C .36487.3589357.70819767.684867741.4033546763.18592832393.65556183495

%H R. H. Hardin, <a href="/A188358/b188358.txt">Table of n, a(n) for n = 1..178</a>

%e Some solutions for n=6 k=4

%e .-4...-1...-4....0....3....0...-1....0...-4...-1...-1...-1...-2...-1....1...-3

%e ..0...-2...-3...-2...-4...-4...-3...-4....0...-1...-2...-3...-2....0...-2...-1

%e .-4....2....3....1....3....4...-3...-1....4....0....1....1...-2....4....1....1

%e ..4...-1...-1....1....3....4....0...-2....0....0...-3...-4....1...-4...-4....2

%e ..4....2....2....1....1....0....1....3...-2...-3...-1...-1...-2...-4....3...-3

%e ..3....1...-2....0...-4....1...-3...-2....0...-1....0....2....1...-4....4...-1

%e .-4....4...-3...-1...-4....0....3...-3...-4....4....3....1...-2....4....2....1

%Y Row 1 is A016813

%Y Row 2 is A014634

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_ Mar 28 2011