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A197051 Number of nX5 0..4 arrays with each element equal to the number its horizontal and vertical zero neighbors. 4
4, 10, 38, 108, 358, 1132, 3580, 11382, 36270, 114992, 365628, 1162290, 3692624, 11733828, 37293892, 118504546, 376583590, 1196750110, 3803034578, 12085297922, 38405269512, 122045123484, 387837623386, 1232482503260, 3916616317912 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

Column 5 of A197054.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +4*a(n-2) +10*a(n-3) +4*a(n-4) -20*a(n-5) +a(n-6) -2*a(n-7) +2*a(n-8) -16*a(n-9) +4*a(n-10) +a(n-13) for n>14.

Equivalent empirical g.f. 4*x -2*x^2*(5+14*x+15*x^2-x^3-39*x^4-8*x^5+6*x^6-21*x^7-13*x^8-x^9+x^10+3*x^11+3*x^12) ) / ( -1+x+4*x^2+10*x^3+4*x^4-20*x^5+x^6-2*x^7+2*x^8-16*x^9+4*x^10+x^13 ). - R. J. Mathar, Oct 10 2011

EXAMPLE

Some solutions for n=4

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

..2..1..0..4..0....0..2..2..0..3....3..0..3..0..2....2..0..2..2..0

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

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

CROSSREFS

Sequence in context: A046562 A240382 A220198 * A149191 A149192 A032123

Adjacent sequences:  A197048 A197049 A197050 * A197052 A197053 A197054

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 09 2011

STATUS

approved

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Last modified October 21 12:44 EDT 2018. Contains 316420 sequences. (Running on oeis4.)