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 A199826 Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and no two neighbors summing to zero 1

%I

%S 10,40,114,426,1650,6126,23206,88636,337866,1295566,4992364,19269156,

%T 74529210,288954786,1122363984,4366362420,17011617426,66365823648,

%U 259213619826,1013542247970,3966939195402,15540399135516,60929935280508

%N Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and no two neighbors summing to zero

%C Column 2 of A199832

%H R. H. Hardin, <a href="/A199826/b199826.txt">Table of n, a(n) for n = 1..200</a>

%e Some solutions for n=3

%e ..0....0...-1....0...-1....1...-1...-1....1....1...-1...-2....0...-2....1....1

%e ..1...-1...-2...-2....2....2....0...-2....0....2...-2....1....2...-2....1...-2

%e .-2...-1....0....0....0....1...-1....1....1....0....1....0...-1....1....0...-1

%e ..1....2....2....2....1...-2....2....1...-2...-1....2....2...-1....2...-2....2

%e ..0....0....1....0...-2...-2....0....1....0...-2....0...-1....0....1....0....0

%K nonn

%O 1,1

%A _R. H. Hardin_ Nov 11 2011

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Last modified April 17 03:58 EDT 2021. Contains 343059 sequences. (Running on oeis4.)