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A207764 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically 1
9, 81, 193, 663, 1664, 4018, 11509, 30943, 79178, 213444, 574517, 1510235, 4016905, 10742833, 28499913, 75702647, 201719465, 536397481, 1425655190, 3793651190, 10091485607, 26833849671, 71376964346, 189863830540, 504956635718 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A207762

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) -3*a(n-2) +15*a(n-3) -28*a(n-4) +16*a(n-5) -51*a(n-6) +83*a(n-7) -21*a(n-8) +65*a(n-9) -150*a(n-10) +64*a(n-11) -54*a(n-12) +132*a(n-13) -76*a(n-14) +26*a(n-15) -40*a(n-16) +20*a(n-17) for n>19

EXAMPLE

Some solutions for n=4

..1..1..1..1....1..1..1..1....1..0..0..1....0..0..1..0....1..1..0..0

..0..1..1..1....0..0..1..0....1..1..1..1....1..1..1..1....1..0..0..1

..0..1..1..0....0..0..1..0....1..0..0..1....0..0..1..0....0..0..1..0

..0..0..1..0....1..1..1..0....1..0..0..1....0..0..1..0....0..1..0..0

CROSSREFS

Sequence in context: A208690 A207342 A207271 * A207662 A207484 A207265

Adjacent sequences:  A207761 A207762 A207763 * A207765 A207766 A207767

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 19 2012

STATUS

approved

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Last modified October 19 11:49 EDT 2021. Contains 348088 sequences. (Running on oeis4.)