cp's OEIS Frontend

A208709 T(n,k)=Number of nXk 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A208709 #7 Jul 22 2025 21:29:12
%S A208709 1,2,2,4,8,4,8,28,32,8,16,100,196,128,16,32,356,1268,1372,512,32,64,
%T A208709 1268,8128,16084,9604,2048,64,128,4516,52184,185344,204020,67228,8192,
%U A208709 128,256,16084,334948,2142580,4226368,2587924,470596,32768,256,512,57284,2149988
%N A208709 T(n,k)=Number of nXk 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A208709 Table starts
%C A208709 ...1.....2.......4.........8..........16............32..............64
%C A208709 ...2.....8......28.......100.........356..........1268............4516
%C A208709 ...4....32.....196......1268........8128.........52184..........334948
%C A208709 ...8...128....1372.....16084......185344.......2142580........24754628
%C A208709 ..16...512....9604....204020.....4226368......87985748......1830045552
%C A208709 ..32..2048...67228...2587924....96373248....3613193828....135288700496
%C A208709 ..64..8192..470596..32826932..2197585152..148378294612..10001404535216
%C A208709 .128.32768.3294172.416398420.50111214592.6093257064980.739367693888784
%H A208709 R. H. Hardin, <a href="/A208709/b208709.txt">Table of n, a(n) for n = 1..631</a>
%e A208709 Some solutions for n=4 k=3
%e A208709 ..0..1..1....0..1..0....0..0..0....0..0..1....0..0..1....0..1..0....0..1..0
%e A208709 ..1..0..0....0..0..0....0..1..1....0..0..0....0..1..1....0..0..0....1..0..0
%e A208709 ..1..0..1....0..1..1....1..0..1....1..1..1....0..0..0....1..1..1....1..0..1
%e A208709 ..1..1..1....0..1..1....0..1..0....0..0..0....0..1..0....1..0..0....1..1..0
%Y A208709 Column 2 is A004171(n-1)
%Y A208709 Row 2 is A104934
%K A208709 nonn,tabl
%O A208709 1,2
%A A208709 _R. H. Hardin_ Mar 01 2012