%I #12 Jan 02 2019 11:26:39
%S 2,7,15,27,55,109,199,347,595,1005,1671,2751,4507,7357,11971,19439,
%T 31531,51105,82779,134031,216967,351169,568315,919667,1488175,2408049,
%U 3896439,6304707,10201375,16506325,26707951,43214531,69922747,113137557
%N Number of (1+1) X (n+1) arrays of permutations of 0..n*2+1 filled by rows with each element moved a city block distance of 0 or 2, and rows and columns in increasing lexicographic order.
%H R. H. Hardin, <a href="/A263603/b263603.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 3*a(n-2) + 2*a(n-3) - a(n-4) - a(n-5) + a(n-6) for n>8.
%F Empirical g.f.: x*(2 + x - x^3 + 7*x^4 + 4*x^5 + 3*x^6 + 2*x^7) / ((1 - x)^2*(1 + x^2)*(1 - x - x^2)). - _Colin Barker_, Jan 02 2019
%e Some solutions for n=4:
%e ..0..3..4..7..8....0..1..2..3..4....0..1..2..3..4....0..1..2..3..4
%e ..1..2..5..6..9....5..6..7..8..9....5..6..9..8..7....7..8..5..6..9
%Y Row 1 of A263602.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 22 2015