cp's OEIS Frontend

A188953 Number of nX2 array permutations with each element moved no more than a city block distance of two.

%I A188953 #7 Jul 22 2025 11:28:31
%S A188953 2,24,362,3969,45288,532224,6187928,71851073,835579642,9715691800,
%T A188953 112952196626,1313218423169,15268015911568,177510903321088,
%U A188953 2063800528041456,23994446285179649,278967524405993266
%N A188953 Number of nX2 array permutations with each element moved no more than a city block distance of two.
%C A188953 Column 2 of A188958
%H A188953 R. H. Hardin, <a href="/A188953/b188953.txt">Table of n, a(n) for n = 1..200</a>
%F A188953 Empirical: a(n) = 10*a(n-1) +7*a(n-2) +156*a(n-3) -169*a(n-4) -410*a(n-5) -17*a(n-6) +576*a(n-7) -271*a(n-8) +310*a(n-9) -119*a(n-10) +68*a(n-11) -7*a(n-12) -6*a(n-13) +a(n-14)
%e A188953 Some solutions for 3X2
%e A188953 ..3..2....1..0....1..2....3..2....1..2....3..1....4..0....1..5....0..1....1..5
%e A188953 ..1..0....3..4....0..4....4..0....0..3....2..0....3..2....4..0....4..2....3..4
%e A188953 ..4..5....2..5....3..5....5..1....5..4....4..5....5..1....2..3....3..5....0..2
%K A188953 nonn
%O A188953 1,1
%A A188953 _R. H. Hardin_ Apr 14 2011