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!)
A304959 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero. 7
0, 1, 1, 1, 7, 1, 2, 16, 16, 2, 3, 45, 42, 45, 3, 5, 120, 118, 118, 120, 5, 8, 333, 371, 496, 371, 333, 8, 13, 928, 1203, 2080, 2080, 1203, 928, 13, 21, 2613, 3917, 8361, 11282, 8361, 3917, 2613, 21, 34, 7400, 12919, 35441, 60568, 60568, 35441, 12919, 7400, 34 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

..0....1.....1......2........3.........5..........8..........13...........21

..1....7....16.....45......120.......333........928........2613.........7400

..1...16....42....118......371......1203.......3917.......12919........42060

..2...45...118....496.....2080......8361......35441......148491.......621640

..3..120...371...2080....11282.....60568.....334906.....1852576.....10208628

..5..333..1203...8361....60568....435964....3174054....23304518....170481467

..8..928..3917..35441...334906...3174054...30361694...294236689...2849022835

.13.2613.12919.148491..1852576..23304518..294236689..3805684538..49133027076

.21.7400.42060.621640.10208628.170481467.2849022835.49133027076.844100991906

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..180

FORMULA

Empirical for column k:

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

k=2: a(n) = 2*a(n-1) +5*a(n-2) -2*a(n-3) -12*a(n-4) -8*a(n-5) for n>6

k=3: [order 20] for n>21

k=4: [order 69] for n>71

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 1 is A000045(n-1).

Column 2 is A304013.

Sequence in context: A316740 A304019 A305367 * A316641 A304697 A316448

Adjacent sequences:  A304956 A304957 A304958 * A304960 A304961 A304962

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, May 22 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 25 17:22 EDT 2021. Contains 348255 sequences. (Running on oeis4.)