A197359 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,1,1,1 for x=0,1,2,3,4

1, 9, 33, 113, 593, 2435, 10317, 45615, 195093, 841571, 3646693, 15718319, 67872219, 293228491, 1265855985, 5466238427, 23604968149, 101924529475, 440126714041, 1900525775017, 8206607484875, 35437081228013, 153021248588503

Offset

1,2

Comments

Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's

Column 3 of A197364

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = a(n-1) +2*a(n-2) +24*a(n-3) +75*a(n-4) +159*a(n-5) +275*a(n-6) -16*a(n-7) +201*a(n-8) -431*a(n-9) -1831*a(n-10) -1919*a(n-11) -7217*a(n-12) -7968*a(n-13) -10020*a(n-14) +68*a(n-15) +19396*a(n-16) +29136*a(n-17) +19536*a(n-18) -12960*a(n-19) -2592*a(n-20)

Example

Some solutions for n=4
..1..3..1....1..3..1....0..0..0....0..0..0....0..1..2....0..1..2....0..2..1
..1..1..0....1..1..2....0..0..1....0..0..0....1..3..1....0..3..1....1..1..3
..3..1..0....3..1..0....0..1..3....1..3..1....0..0..0....0..1..2....3..1..1
..1..2..0....1..0..0....0..2..1....0..1..0....0..0..0....0..0..0....1..2..0

Crossrefs

Sequence in context: A147107 A147115 A147261 * A147155 A146232 A146180

Adjacent sequences: A197356 A197357 A197358 * A197360 A197361 A197362

Keyword

nonn

Author

R. H. Hardin Oct 14 2011

Status

approved