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A222878 T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

%I A222878 #6 Jul 23 2025 03:11:59
%S A222878 1,1,2,2,11,5,11,122,131,15,34,1814,6282,2150,51,131,26311,409775,
%T A222878 443510,32491,187,438,399849,19707855,95867967,23794078,533186,715,
%U A222878 2150,6013669,1340197778,20978414941,22794825314,1698174722,8362152,2795,7676
%N A222878 T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
%C A222878 Table starts
%C A222878 .....1..........1...............2...................11......................34
%C A222878 .....2.........11.............122.................1814...................26311
%C A222878 .....5........131............6282...............409775................19707855
%C A222878 ....15.......2150..........443510.............95867967.............20978414941
%C A222878 ....51......32491........23794078..........22794825314..........16473931317022
%C A222878 ...187.....533186......1698174722........5472896849943.......17791003053622809
%C A222878 ...715....8362152.....93656293632.....1322676376672081....14337592109053271558
%C A222878 ..2795..135650378...6637413406814...321195816580955511.15577784123509878927189
%C A222878 .11051.2155759835.372075279639542.78284744747263499257
%H A222878 R. H. Hardin, <a href="/A222878/b222878.txt">Table of n, a(n) for n = 1..82</a>
%e A222878 Some solutions for n=3 k=4
%e A222878 ..0..0..0..1....0..0..1..0....0..0..1..2....0..1..0..1....0..1..0..2
%e A222878 ..2..3..1..2....0..2..2..3....1..3..1..0....0..2..2..2....1..0..1..3
%e A222878 ..0..2..3..0....0..3..2..1....1..2..0..2....1..0..0..0....2..0..2..1
%Y A222878 Column 1 is A007581(n-1)
%Y A222878 Row 1 is A222650
%K A222878 nonn,tabl
%O A222878 1,3
%A A222878 _R. H. Hardin_ Mar 08 2013