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A231137 T(n,k)=Number of (n+1)X(k+1) black-square subarrays of 0..2 arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order 5
1, 2, 2, 6, 9, 6, 16, 40, 40, 16, 44, 182, 308, 182, 44, 120, 808, 2260, 2260, 808, 120, 328, 3688, 16812, 27171, 16812, 3688, 328, 896, 16368, 124644, 336004, 336004, 124644, 16368, 896, 2448, 74728, 924900, 4066129, 6794904, 4066129, 924900, 74728, 2448 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

..1...2.....6.....16......44.......120........328.........896..........2448

..2...9....40....182.....808......3688......16368.......74728........331648

..6..40...308...2260...16812....124644.....924900.....6862052......50913012

.16.182..2260..27171..336004...4066129...50257244...608468617....7520563372

.44.808.16812.336004.6794904.137063228.2766762720.55844298404.1127200291672

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..312

FORMULA

Empirical for column k:

k=1: a(n) = 2*a(n-1) +2*a(n-2)

k=2: a(n) = 22*a(n-2) -36*a(n-4) +16*a(n-6)

k=3: [order 8]

k=4: [order 18, even terms]

k=5: [order 34]

k=6: [order 90, even terms]

EXAMPLE

Some solutions for n=2 k=4

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

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

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

CROSSREFS

Column 1 is A002605

Column 3 is A231126

Column 5 is A231128

Column 7 is A231130

Sequence in context: A169800 A094485 A242978 * A188808 A021819 A000021

Adjacent sequences:  A231134 A231135 A231136 * A231138 A231139 A231140

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 04 2013

STATUS

approved

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Last modified June 17 17:03 EDT 2019. Contains 324196 sequences. (Running on oeis4.)