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A202658 Number of -2..2 arrays of n elements with first through fourth differences also in -2..2.

%I A202658 #8 Jun 02 2025 07:26:13
%S A202658 5,19,57,127,213,363,613,1055,1815,3159,5503,9609,16773,29281,51125,
%T A202658 89277,155899,272315,475793,831415,1452927,2539213,4437877,7756367,
%U A202658 13556573,23694815,41415935,72391801,126536987,221182305,386622379
%N A202658 Number of -2..2 arrays of n elements with first through fourth differences also in -2..2.
%C A202658 Column 2 of A202664
%H A202658 R. H. Hardin, <a href="/A202658/b202658.txt">Table of n, a(n) for n = 1..210</a>
%F A202658 Empirical: a(n) = a(n-1) +2*a(n-3) +2*a(n-4) -a(n-5) -2*a(n-7) -a(n-8) -4*a(n-10) -7*a(n-11) -10*a(n-12) -7*a(n-13) -6*a(n-14) -a(n-15) +6*a(n-16) +9*a(n-17) +8*a(n-18) +6*a(n-19) +4*a(n-20) +2*a(n-21) for n>27
%e A202658 Some solutions for n=10
%e A202658 .-2...-2....1...-2....0....0...-1....0....0....1...-2....1....0....1...-2....2
%e A202658 ..0...-1....2....0...-1....1....1....2....0...-1....0....0...-2....2....0....2
%e A202658 ..0....0....2....0....0....0....1....2...-1...-2....1...-1...-2....2....0....1
%e A202658 ..0....1....2...-1....1...-1....0....1...-1...-2....2...-1...-2....2...-1....0
%e A202658 ..0....1....2...-1....2...-2...-1....0....0...-2....2...-1...-2....2...-2....0
%e A202658 ..0....1....2....0....2...-2...-1....0....1...-2....2...-1...-1....1...-2....1
%e A202658 ..1....1....1....1....2...-1...-1....0....2...-2....1...-1....1....0...-1....2
%e A202658 ..2....0...-1....1....2....0...-1....0....2...-1....0....0....2....0....0....2
%e A202658 ..2...-1...-2....1....1....0....0....0....1....0...-1....1....2....0....1....1
%e A202658 ..1...-2...-2....0...-1....0....1....1....0....1...-1....0....2...-1....1....0
%K A202658 nonn
%O A202658 1,1
%A A202658 _R. H. Hardin_ Dec 22 2011