A232917 - OEIS

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A232917

Number of n X 5 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally, diagonally or antidiagonally.

48, 396, 3612, 33702, 316800, 2986152, 28178262, 266016264, 2511769872, 23718269934, 223974692940, 2115047273040, 19973000452170, 188611165560264, 1781114471948484, 16819628783052894, 158833109275938936

(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) = 14*a(n-1) - 45*a(n-2) + 15*a(n-3) + 36*a(n-4) - 19*a(n-5) + 2*a(n-6).

Empirical g.f.: 6*x*(4 - 7*x + x^2)*(2 - 8*x - 5*x^2 + 3*x^3) / (1 - 14*x + 45*x^2 - 15*x^3 - 36*x^4 + 19*x^5 - 2*x^6). - Colin Barker, Oct 06 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 5 of A232920.

Sequence in context: A160335 A019558 A339761 * A172201 A249293 A347168

Adjacent sequences: A232914 A232915 A232916 * A232918 A232919 A232920

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 02 2013

STATUS

approved