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A207024 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically 12
2, 4, 4, 6, 16, 6, 9, 36, 36, 8, 13, 81, 90, 64, 10, 18, 169, 252, 168, 100, 12, 25, 324, 624, 558, 270, 144, 14, 34, 625, 1350, 1586, 1035, 396, 196, 16, 46, 1156, 3025, 3726, 3315, 1719, 546, 256, 18, 62, 2116, 6256, 9450, 8280, 6123, 2646, 720, 324, 20, 83, 3844 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

..2...4...6....9....13....18.....25.....34......46......62.......83......111

..4..16..36...81...169...324....625...1156....2116....3844.....6889....12321

..6..36..90..252...624..1350...3025...6256...12788...25792....50630....99012

..8..64.168..558..1586..3726...9450..21318...47518..104470...220531...464202

.10.100.270.1035..3315..8280..23400..56814..136114..322834...725005..1627260

.12.144.396.1719..6123.16038..49925.129302..329498..836938..1984447..4716834

.14.196.546.2646.10374.28224..95900.263228..707756.1914436..4765030.11929281

.16.256.720.3852.16484.46260.170300.492932.1389476.3984244.10362550.27202659

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..1984

FORMULA

Empirical for column k:

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

k=2: a(n) = 4*n^2

k=3: a(n) = 12*n^2 - 6*n

k=4: a(n) = 6*n^3 + (27/2)*n^2 - (21/2)*n

k=5: a(n) = (13/6)*n^4 + 13*n^3 + (52/3)*n^2 - (39/2)*n

k=6: a(n) = (33/4)*n^4 + (45/2)*n^3 + (75/4)*n^2 - (63/2)*n

k=7: a(n) = (55/24)*n^5 + (75/4)*n^4 + (275/8)*n^3 + (75/4)*n^2 - (295/6)*n

EXAMPLE

Some solutions for n=4 k=3

..1..0..0....0..1..0....0..0..1....1..0..1....0..0..1....1..1..0....1..1..1

..1..0..0....1..1..0....1..1..1....0..0..1....0..0..1....1..0..1....1..1..1

..1..0..0....1..1..0....0..0..1....0..0..1....0..0..1....1..0..1....0..1..0

..1..0..0....1..0..0....0..0..1....0..0..1....0..0..1....0..0..1....0..1..0

CROSSREFS

Column 2 is A016742

Column 3 is A152746

Row 1 is A171861(n+1)

Sequence in context: A207254 A207403 A208142 * A207169 A207111 A207305

Adjacent sequences:  A207021 A207022 A207023 * A207025 A207026 A207027

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Feb 14 2012

STATUS

approved

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Last modified August 14 13:57 EDT 2020. Contains 336481 sequences. (Running on oeis4.)