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A295275 T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1 or 4 1s. 7
2, 4, 4, 7, 11, 7, 13, 33, 33, 13, 24, 98, 164, 98, 24, 44, 291, 811, 811, 291, 44, 81, 865, 4035, 6659, 4035, 865, 81, 149, 2570, 19997, 54773, 54773, 19997, 2570, 149, 274, 7637, 99245, 449827, 748740, 449827, 99245, 7637, 274, 504, 22693, 492401, 3697742 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

...2.....4.......7........13..........24............44..............81

...4....11......33........98.........291...........865............2570

...7....33.....164.......811........4035.........19997...........99245

..13....98.....811......6659.......54773........449827.........3697742

..24...291....4035.....54773......748740......10203847.......139221499

..44...865...19997....449827....10203847.....230659662......5221177246

..81..2570...99245...3697742...139221499....5221177246....196091375073

.149..7637..492401..30386185..1898916677..118139247475...7361533108317

.274.22693.2443097.249719021.25902054180.2673342943199.276386201580189

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..419

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1) +a(n-2) +a(n-3)

k=2: a(n) = 2*a(n-1) +3*a(n-2) -a(n-4)

k=3: [order 10]

k=4: [order 16]

k=5: [order 40]

k=6: [order 78]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Column 1 is A000073(n+3).

Column 2 is A282990.

Sequence in context: A296578 A268750 A282996 * A295253 A295652 A269075

Adjacent sequences:  A295272 A295273 A295274 * A295276 A295277 A295278

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 19 2017

STATUS

approved

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Last modified September 16 20:51 EDT 2021. Contains 347473 sequences. (Running on oeis4.)