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A180760 T(n,k)=half the number of nXk binary arrays with each element equal to at least two neighbors.

%I A180760 #5 Jul 22 2025 08:29:07
%S A180760 0,0,0,0,1,0,0,1,1,0,0,2,1,2,0,0,3,2,2,3,0,0,5,3,9,3,5,0,0,8,7,21,21,
%T A180760 7,8,0,0,13,14,70,86,70,14,13,0,0,21,31,207,410,410,207,31,21,0,0,34,
%U A180760 67,658,1874,2986,1874,658,67,34,0,0,55,148,2059,8840,20205,20205,8840,2059,148
%N A180760 T(n,k)=half the number of nXk binary arrays with each element equal to at least two neighbors.
%C A180760 Table starts
%C A180760 .0..0...0....0......0.......0.........0..........0............0.............0
%C A180760 .0..1...1....2......3.......5.........8.........13...........21............34
%C A180760 .0..1...1....2......3.......7........14.........31...........67...........148
%C A180760 .0..2...2....9.....21......70.......207........658.........2059..........6521
%C A180760 .0..3...3...21.....86.....410......1874.......8840........41755........197883
%C A180760 .0..5...7...70....410....2986.....20205.....141313.......986376.......6925085
%C A180760 .0..8..14..207...1874...20205....205020....2141384.....22238670.....232041425
%C A180760 .0.13..31..658...8840..141313...2141384...33329847....514990479....7988200496
%C A180760 .0.21..67.2059..41755..986376..22238670..514990479..11843513563..273193577866
%C A180760 .0.34.148.6521.197883.6925085.232041425.7988200496.273193577866.9371551715962
%H A180760 R. H. Hardin, <a href="/A180760/b180760.txt">Table of n, a(n) for n=1..264</a>
%K A180760 nonn,tabl
%O A180760 1,12
%A A180760 _R. H. Hardin_ Sep 20 2010