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A239820 Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it, modulo 4 1
5, 23, 132, 729, 3951, 21602, 118253, 646306, 3532732, 19315270, 105601487, 577330665, 3156353205, 17256335056, 94343160597, 515789128277, 2819903064231, 15416868881838, 84286524854294, 460808121256380, 2519312876415017 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A239819

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -28*a(n-2) +74*a(n-3) -181*a(n-4) +236*a(n-5) -261*a(n-6) +234*a(n-7) +200*a(n-8) -279*a(n-9) +104*a(n-10) -268*a(n-11) -36*a(n-12) +156*a(n-13) +104*a(n-14) -32*a(n-15) -16*a(n-16)

EXAMPLE

Some solutions for n=5

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

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

CROSSREFS

Sequence in context: A186755 A009321 A078509 * A077240 A281231 A244786

Adjacent sequences:  A239817 A239818 A239819 * A239821 A239822 A239823

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 27 2014

STATUS

approved

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Last modified December 3 20:56 EST 2020. Contains 338920 sequences. (Running on oeis4.)