The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A303803 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing all changes.

A303803

Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 4 king-move adjacent elements, with upper left element zero.
(history; published version)

#4 by R. H. Hardin at Mon Apr 30 17:19:15 EDT 2018

STATUS

editing

approved

#3 by R. H. Hardin at Mon Apr 30 17:19:12 EDT 2018

LINKS

R. H. Hardin, <a href="/A303803/b303803.txt">Table of n, a(n) for n = 1..210</a>

#2 by R. H. Hardin at Mon Apr 30 17:18:57 EDT 2018

NAME

allocated for R. H. Hardin

Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 4 king-move adjacent elements, with upper left element zero.

DATA

3, 7, 9, 15, 27, 47, 83, 161, 321, 641, 1293, 2665, 5603, 11957, 25767, 55917, 122063, 267835, 590085, 1303845, 2886875, 6401619, 14212171, 31580661, 70221799, 156218863, 347655099, 773886975, 1723025065, 3836799089, 8544630497

OFFSET

1,1

COMMENTS

Column 3 of A303808.

FORMULA

Empirical: a(n) = 3*a(n-1) -a(n-2) -3*a(n-3) +6*a(n-4) -5*a(n-5) -2*a(n-6) -a(n-7) -6*a(n-8) +4*a(n-9) +2*a(n-10)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303808.

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin, Apr 30 2018

STATUS

approved

editing

#1 by R. H. Hardin at Mon Apr 30 17:17:02 EDT 2018

NAME

allocated for R. H. Hardin

KEYWORD

allocated

STATUS

approved