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!)
A278280 T(n,k)=Number of nXk 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero. 14
0, 0, 0, 0, 2, 0, 0, 4, 5, 0, 0, 13, 25, 16, 0, 0, 36, 122, 136, 49, 0, 0, 109, 661, 1461, 839, 153, 0, 0, 317, 3723, 15728, 16842, 5013, 476, 0, 0, 938, 20736, 172091, 350649, 196726, 30370, 1483, 0, 0, 2754, 115446, 1870365, 7466627, 7974561, 2293193 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0.....0.......0..........0.............0................0..................0

.0.....2.......4.........13............36..............109................317

.0.....5......25........122...........661.............3723..............20736

.0....16.....136.......1461.........15728...........172091............1870365

.0....49.....839......16842........350649..........7466627..........157609938

.0...153....5013.....196726.......7974561........329985827........13538466880

.0...476...30370....2293193.....180592726......14526103064......1158266740087

.0..1483..183403...26748095....4093629985.....640011857446.....99182079495633

.0..4619.1108525..311952675...92770708201...28192246592564...8491049196878995

.0.14388.6699034.3638315600.2102508396678.1241921389868057.726961954823301592

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..287

FORMULA

Empirical for column k:

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

k=3: a(n) = 6*a(n-1) +3*a(n-2) -17*a(n-3) +19*a(n-5) -16*a(n-6) +8*a(n-7) for n>9

k=4: [order 17] for n>19

k=5: [order 44] for n>46

k=6: [order 98] for n>101

Empirical for row n:

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

n=3: [order 16]

n=4: [order 40]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Sequence in context: A115179 A131742 A257813 * A213370 A244138 A284611

Adjacent sequences:  A278277 A278278 A278279 * A278281 A278282 A278283

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 16 2016

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 January 25 01:10 EST 2021. Contains 340414 sequences. (Running on oeis4.)