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A231023 T(n,k)=Number of (n+3)X(k+3) 0..3 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 4, and upper left element zero 5
6, 16, 16, 76, 242, 76, 314, 724, 724, 314, 1170, 10534, 8374, 10534, 1170, 4584, 28128, 85196, 85196, 28128, 4584, 18208, 419878, 854206, 3160834, 854206, 419878, 18208, 71242, 1144652, 8838040, 22328204, 22328204, 8838040, 1144652, 71242, 278758 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....6.......16........76..........314...........1170.............4584

....16......242.......724........10534..........28128...........419878

....76......724......8374........85196.........854206..........8838040

...314....10534.....85196......3160834.......22328204........859128648

..1170....28128....854206.....22328204......584293702......15744800360

..4584...419878...8838040....859128648....15744800360....1576885946694

.18208..1144652..91616256...6209914254...421312592376...29418861515276

.71242.16946918.944382122.235891268252.11212196319546.2914693904795344

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..143

FORMULA

Empirical for column k:

k=1: a(n) = 3*a(n-1) +14*a(n-3) +a(n-4) -a(n-5)

k=2: [order 16]

k=3: [order 30]

k=4: [order 70]

EXAMPLE

Some solutions for n=2 k=4

..x..0..x..3..x..3..x....x..0..x..0..x..0..x....x..0..x..2..x..2..x

..1..x..3..x..0..x..0....3..x..1..x..3..x..1....0..x..1..x..3..x..1

..x..2..x..3..x..1..x....x..0..x..2..x..2..x....x..1..x..0..x..2..x

..3..x..1..x..0..x..2....3..x..3..x..1..x..1....2..x..0..x..3..x..1

..x..0..x..3..x..3..x....x..2..x..0..x..0..x....x..3..x..2..x..2..x

CROSSREFS

Column 1 is A230942

Column 3 is A230944

Column 5 is A230946

Column 7 is A230948

Sequence in context: A183127 A222884 A230949 * A217186 A101239 A242331

Adjacent sequences:  A231020 A231021 A231022 * A231024 A231025 A231026

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 03 2013

STATUS

approved

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Last modified May 25 05:45 EDT 2022. Contains 354048 sequences. (Running on oeis4.)