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A202078 Number of arrays of 7 integers in -n..n with sum zero and the sum of every adjacent pair being odd 1

%I

%S 6,96,1014,3752,15010,35604,95342,181834,390544,654086,1221708,

%T 1876930,3183404,4598874,7268148,10026924,15014418,19984692,28678218,

%U 37094052,51428190,64980344,87564274,108501126,142759916,173998474,224327824

%N Number of arrays of 7 integers in -n..n with sum zero and the sum of every adjacent pair being odd

%C Row 5 of A202076

%H R. H. Hardin, <a href="/A202078/b202078.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +6*a(n-2) -6*a(n-3) -15*a(n-4) +15*a(n-5) +20*a(n-6) -20*a(n-7) -15*a(n-8) +15*a(n-9) +6*a(n-10) -6*a(n-11) -a(n-12) +a(n-13)

%e Some solutions for n=3

%e ..1...-1....3....1...-3...-3....3....3....1...-3....1....1....3...-1...-1...-1

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

%e ..1....1....1...-1....1...-1...-3....1...-3....1....1....3....1....1....3...-1

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

%e .-3....1....1....1....1....3....3....3...-1....3...-3...-3...-3....3...-1...-1

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

%e .-1...-3...-3....1....1....3....3...-1....1....1....1....1....1....1....1....1

%K nonn

%O 1,1

%A _R. H. Hardin_ Dec 10 2011

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Last modified September 26 12:17 EDT 2022. Contains 356997 sequences. (Running on oeis4.)