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A202966 Number of arrays of 6 integers in -n..n with sum zero and adjacent elements differing in absolute value.

%I A202966 #7 Jul 22 2025 16:54:10
%S A202966 0,200,1936,9884,33736,90604,207184,421620,785504,1366876,2251016,
%T A202966 3543320,5371856,7888384,11270788,15726488,21492408,28838244,38069472,
%U A202966 49527504,63592532,80687412,101276728,125870512,155027684,189355324
%N A202966 Number of arrays of 6 integers in -n..n with sum zero and adjacent elements differing in absolute value.
%C A202966 Row 4 of A202962
%H A202966 R. H. Hardin, <a href="/A202966/b202966.txt">Table of n, a(n) for n = 1..210</a>
%F A202966 Empirical: a(n) = 2*a(n-1) -3*a(n-4) +a(n-5) +a(n-6) +a(n-9) +a(n-10) -3*a(n-11) +2*a(n-14) -a(n-15)
%e A202966 Some solutions for n=5
%e A202966 .-2....4....2...-1....3....2...-4...-4....2...-1....2...-5....3...-3...-4....1
%e A202966 ..1....1....5....3...-4....0....0...-2....4...-2....4....3....4...-5....5...-2
%e A202966 ..5....2...-3...-4...-5...-1....4....5...-2...-3...-2...-2...-1...-2....4....5
%e A202966 ..3...-3....0....1....0....0....3....2...-5...-1...-3....3...-5....4....2....2
%e A202966 .-5....1...-4....3....4...-1...-1...-4....0....3...-1....0....0....5...-5...-4
%e A202966 .-2...-5....0...-2....2....0...-2....3....1....4....0....1...-1....1...-2...-2
%K A202966 nonn
%O A202966 1,2
%A A202966 _R. H. Hardin_ Dec 26 2011