login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A296335 T(n,k)=Number of nXk 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 0 or 2 neighboring 1s. 8
2, 3, 3, 5, 8, 5, 8, 19, 19, 8, 13, 47, 64, 47, 13, 21, 116, 230, 230, 116, 21, 34, 286, 816, 1235, 816, 286, 34, 55, 705, 2895, 6504, 6504, 2895, 705, 55, 89, 1738, 10277, 34224, 50595, 34224, 10277, 1738, 89, 144, 4285, 36480, 180404, 392230, 392230, 180404 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

..2....3......5.......8........13.........21...........34............55

..3....8.....19......47.......116........286..........705..........1738

..5...19.....64.....230.......816.......2895........10277.........36480

..8...47....230....1235......6504......34224.......180404........950451

.13..116....816....6504.....50595.....392230......3051494......23717411

.21..286...2895...34224....392230....4476519.....51335713.....587914968

.34..705..10277..180404...3051494...51335713....869077778...14686634221

.55.1738..36480..950451..23717411..587914968..14686634221..366077961514

.89.4285.129486.5007796.184355308.6733523523.248214082895.9126072558650

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)

k=2: a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +2*a(n-4) +a(n-5)

k=3: a(n) = 2*a(n-1) +4*a(n-2) +5*a(n-3) +2*a(n-4) -2*a(n-5) -3*a(n-6) -2*a(n-7) +a(n-9)

k=4: [order 21]

k=5: [order 44]

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 1 is A000045(n+2).

Sequence in context: A153643 A053218 A198335 * A296635 A295051 A295379

Adjacent sequences:  A296332 A296333 A296334 * A296336 A296337 A296338

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 10 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 12 09:23 EDT 2020. Contains 335657 sequences. (Running on oeis4.)