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A230949 T(n,k)=Number of (n+3)X(k+3) 0..3 white 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 9
6, 16, 16, 76, 34, 76, 314, 724, 724, 314, 1170, 1994, 8374, 1994, 1170, 4584, 28128, 85196, 85196, 28128, 4584, 18208, 76682, 854206, 606224, 854206, 76682, 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......34.......724........1994..........28128...........76682

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

...314....1994.....85196......606224.......22328204.......161835904

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

..4584...76682...8838040...161835904....15744800360....295706164414

.18208.1144652..91616256..6209914254...421312592376..29418861515276

.71242.3107746.944382122.44707108238.11212196319546.546918612768188

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..112

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

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

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

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

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

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

CROSSREFS

Sequence in context: A301831 A183127 A222884 * A231023 A217186 A101239

Adjacent sequences:  A230946 A230947 A230948 * A230950 A230951 A230952

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 01 2013

STATUS

approved

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Last modified May 20 07:42 EDT 2022. Contains 353852 sequences. (Running on oeis4.)