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A301330 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 10, 7, 10, 1, 1, 13, 18, 18, 13, 1, 1, 42, 25, 45, 25, 42, 1, 1, 74, 89, 143, 143, 89, 74, 1, 1, 188, 233, 414, 664, 414, 233, 188, 1, 1, 387, 552, 1481, 2520, 2520, 1481, 552, 387, 1, 1, 885, 1559, 5062, 12342, 17491, 12342, 5062, 1559, 885, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.1...1....1.....1......1.......1........1..........1...........1............1

.1...3....2....10.....13......42.......74........188.........387..........885

.1...2....7....18.....25......89......233........552........1559.........4206

.1..10...18....45....143.....414.....1481.......5062.......17879........62112

.1..13...25...143....664....2520....12342......59524......283455......1368684

.1..42...89...414...2520...17491...116017.....770874.....5227338.....35859578

.1..74..233..1481..12342..116017..1127238...10358770....99285038....951443834

.1.188..552..5062..59524..770874.10358770..135428462..1814828567..24270760178

.1.387.1559.17879.283455.5227338.99285038.1814828567.34057380439.641360375141

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..219

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1)

k=2: a(n) = 4*a(n-2) +2*a(n-3) +a(n-5) -3*a(n-6) +a(n-7)

k=3: [order 28] for n>29

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A300374.

Sequence in context: A300380 A300682 A300605 * A175636 A204253 A064048

Adjacent sequences:  A301327 A301328 A301329 * A301331 A301332 A301333

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 18 2018

STATUS

approved

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Last modified September 25 23:23 EDT 2020. Contains 337346 sequences. (Running on oeis4.)