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A186842 Number of (n+1) X 2 binary arrays with no 2 X 2 subblock diagonal sum less antidiagonal sum equal to any horizontal or vertical neighbor 2 X 2 subblock diagonal sum less antidiagonal sum. 1
16, 50, 162, 512, 1626, 5182, 16476, 52378, 166634, 529984, 1685474, 5360790, 17050124, 54227106, 172469170, 548538048, 1744617610, 5548740302, 17647726972, 56128428362, 178515953178, 567768430400, 1805782389330, 5743274639206 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A186850.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = a(n-1) + 3*a(n-2) + 10*a(n-3) + 8*a(n-4).

Empirical g.f.: 2*x*(8 + 17*x + 32*x^2 + 20*x^3) / (1 - x - 3*x^2 - 10*x^3 - 8*x^4). - Colin Barker, Apr 19 2018

EXAMPLE

Some solutions for 3 X 2:

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

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

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

CROSSREFS

Cf. A186850.

Sequence in context: A235573 A186850 A235566 * A231840 A199809 A121863

Adjacent sequences:  A186839 A186840 A186841 * A186843 A186844 A186845

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 27 2011

STATUS

approved

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Last modified October 14 00:09 EDT 2019. Contains 327990 sequences. (Running on oeis4.)