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A230739 T(n,k)=Number of (n+3)X(k+3) 0..2 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero 6

%I #4 Oct 28 2013 20:30:22

%S 2,8,8,30,66,30,102,244,244,102,348,2016,2106,2016,348,1172,6576,

%T 16536,16536,6576,1172,3956,54138,130446,320970,130446,54138,3956,

%U 13326,173428,1025430,2382398,2382398,1025430,173428,13326,44916,1427040,8053490

%N T(n,k)=Number of (n+3)X(k+3) 0..2 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero

%C Table starts

%C .....2.......8.......30........102..........348...........1172.............3956

%C .....8......66......244.......2016.........6576..........54138...........173428

%C ....30.....244.....2106......16536.......130446........1025430..........8053490

%C ...102....2016....16536.....320970......2382398.......46599682........342031378

%C ...348....6576...130446....2382398.....43853402......801845362......14669811856

%C ..1172...54138..1025430...46599682....801845362....36695929036.....625553036008

%C ..3956..173428..8053490..342031378..14669811856...625553036008...26681634560690

%C .13326.1427040.63237238.6692078688.268320990890.28644012159382.1137681116923966

%H R. H. Hardin, <a href="/A230739/b230739.txt">Table of n, a(n) for n = 1..199</a>

%F Empirical for column k:

%F k=1: a(n) = 3*a(n-1) +3*a(n-2) -6*a(n-3) +a(n-5)

%F k=2: a(n) = 31*a(n-2) -126*a(n-4) +42*a(n-6) +79*a(n-8) -a(n-10) +8*a(n-12)

%F k=3: [order 22]

%F k=4: [order 50]

%e Some solutions for n=3 k=4

%e ..x..0..x..0..x..2..x....x..0..x..2..x..2..x....x..0..x..0..x..1..x

%e ..1..x..1..x..1..x..0....2..x..1..x..0..x..1....1..x..1..x..2..x..0

%e ..x..2..x..0..x..1..x....x..0..x..1..x..1..x....x..2..x..0..x..2..x

%e ..1..x..0..x..2..x..0....1..x..0..x..2..x..0....1..x..0..x..2..x..0

%e ..x..2..x..1..x..1..x....x..2..x..0..x..2..x....x..2..x..1..x..1..x

%e ..1..x..1..x..0..x..0....1..x..2..x..1..x..1....1..x..0..x..0..x..0

%Y Column 1 is A230701

%Y Column 3 is A230703

%Y Column 5 is A230705

%Y Column 7 is A230707

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Oct 28 2013

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Last modified March 28 05:02 EDT 2024. Contains 371235 sequences. (Running on oeis4.)