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A239249 Number of n X 1 0..4 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it, modulo 5. 1
4, 13, 41, 131, 419, 1339, 4279, 13675, 43703, 139667, 446351, 1426459, 4558711, 14568835, 46559423, 148795691, 475524743, 1519693075, 4856670607, 15521061307, 49602570071, 158521051427, 506605276895, 1619020970827, 5174105015335 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) + 2*a(n-3).

Empirical g.f.: x*(4 + x + 2*x^2) / (1 - 3*x - 2*x^3). - Colin Barker, Oct 25 2018

EXAMPLE

Some solutions for n=5:

..4....3....2....3....2....0....4....2....0....3....3....0....3....0....4....4

..2....2....2....2....2....2....3....4....3....0....2....0....2....4....4....3

..4....4....2....0....3....4....0....4....0....2....4....2....0....2....2....4

..0....2....3....4....2....3....2....0....2....0....3....0....0....3....0....0

..3....4....4....4....4....4....2....2....3....4....2....4....2....3....3....4

CROSSREFS

Column 1 of A239256.

Sequence in context: A190214 A052529 A049222 * A141364 A001453 A005002

Adjacent sequences:  A239246 A239247 A239248 * A239250 A239251 A239252

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 13 2014

STATUS

approved

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Last modified January 21 02:59 EST 2019. Contains 319344 sequences. (Running on oeis4.)