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!)
A301325 Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
1, 2, 7, 18, 25, 89, 233, 552, 1559, 4206, 11455, 31045, 85231, 232290, 634523, 1734730, 4739443, 12951941, 35393517, 96729068, 264330489, 722375126, 1974122009, 5394894605, 14743271905, 40290668634, 110107068099, 300902363502 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A301330.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = a(n-1) +3*a(n-2) +6*a(n-3) -6*a(n-5) -9*a(n-6) +7*a(n-7) -15*a(n-8) -14*a(n-9) -20*a(n-10) +30*a(n-11) +3*a(n-12) +47*a(n-13) -67*a(n-14) +38*a(n-15) +15*a(n-16) -65*a(n-17) +106*a(n-18) -83*a(n-19) +24*a(n-20) +13*a(n-21) -32*a(n-22) +29*a(n-23) -11*a(n-24) +3*a(n-26) -3*a(n-27) +a(n-28) for n>29

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A301330.

Sequence in context: A217253 A268837 A104310 * A001114 A107615 A195605

Adjacent sequences:  A301322 A301323 A301324 * A301326 A301327 A301328

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 18 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 August 5 07:25 EDT 2020. Contains 336209 sequences. (Running on oeis4.)