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!)
A304479 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 4 or 6 king-move adjacent elements, with upper left element zero. 7
1, 2, 2, 4, 4, 4, 8, 12, 12, 8, 16, 24, 19, 24, 16, 32, 64, 37, 37, 64, 32, 64, 184, 94, 110, 94, 184, 64, 128, 432, 202, 297, 297, 202, 432, 128, 256, 1088, 428, 869, 931, 869, 428, 1088, 256, 512, 2944, 965, 2325, 2870, 2870, 2325, 965, 2944, 512, 1024, 7360, 2134 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

...1....2....4.....8....16.....32......64......128......256.......512

...2....4...12....24....64....184.....432.....1088.....2944......7360

...4...12...19....37....94....202.....428......965.....2134......4692

...8...24...37...110...297....869....2325.....6379....17568.....48401

..16...64...94...297...931...2870....8058....25040....76568....231646

..32..184..202...869..2870..11079...35462...133597...471114...1710896

..64..432..428..2325..8058..35462..132348...573938..2341508...9662652

.128.1088..965..6379.25040.133597..573938..2942145.13964485..67899747

.256.2944.2134.17568.76568.471114.2341508.13964485.77098563.429574178

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..220

FORMULA

Empirical for column k:

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

k=2: a(n) = 2*a(n-1) +8*a(n-3) -8*a(n-4) -8*a(n-5) for n>6

k=3: [order 12] for n>13

k=4: [order 65] for n>67

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 1 is A000079(n-1).

Column 2 is A303794.

Sequence in context: A033740 A303800 A305245 * A316304 A304848 A316545

Adjacent sequences:  A304476 A304477 A304478 * A304480 A304481 A304482

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, May 13 2018

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 October 20 14:24 EDT 2021. Contains 348108 sequences. (Running on oeis4.)