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A231105 Number of n X 5 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero. 1
0, 20, 286, 4674, 75346, 1217338, 19662930, 317613674, 5130366434, 82870087802, 1338588795186, 21622035453578, 349257679719938, 5641509890213146, 91126511137632082, 1471953642505880106, 23776258946350540066 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

Empirical: a(n) = 14*a(n-1) + 35*a(n-2) - 4*a(n-3) + 4*a(n-4) + 32*a(n-5) - 32*a(n-6).

Empirical g.f.: 2*x^2*(10 + 3*x - 15*x^2 - 10*x^3 - 16*x^4) / ((1 + 2*x)*(1 - 16*x - 3*x^2 + 10*x^3 - 24*x^4 + 16*x^5)). - Colin Barker, Sep 26 2018

EXAMPLE

Some solutions for n=4:

..0..1..0..1..2....0..1..2..3..2....0..1..0..1..2....0..1..2..3..2

..2..3..2..3..0....0..3..0..1..0....2..3..0..3..0....2..3..0..1..2

..0..1..2..1..0....0..1..0..3..0....0..1..2..1..0....2..3..0..3..2

..0..1..2..3..2....2..3..2..1..0....0..3..0..3..2....0..1..2..1..0

CROSSREFS

Column 5 of A231108.

Sequence in context: A016317 A021404 A046175 * A016314 A021164 A225829

Adjacent sequences:  A231102 A231103 A231104 * A231106 A231107 A231108

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 03 2013

STATUS

approved

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Last modified May 30 23:58 EDT 2020. Contains 334747 sequences. (Running on oeis4.)