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A206262 Number of (n+1) X 4 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock equal to the number in all its horizontal and vertical neighbors. 1
34, 44, 78, 135, 218, 339, 503, 724, 1009, 1374, 1828, 2389, 3068, 3885, 4853, 5994, 7323, 8864, 10634, 12659, 14958, 17559, 20483, 23760, 27413, 31474, 35968, 40929, 46384, 52369, 58913, 66054, 73823, 82260, 91398, 101279, 111938, 123419, 135759 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A206267.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + 5*a(n-4) - 4*a(n-5) + a(n-6) for n>7.

Conjectures from Colin Barker, Jun 15 2018: (Start)

G.f.: x*(34 - 92*x + 72*x^2 + 43*x^3 - 102*x^4 + 58*x^5 - 11*x^6) / ((1 - x)^5*(1 + x)).

a(n) = (336 + 154*n + 71*n^2 + 14*n^3 + n^4) / 24 for n>1 and even.

a(n) = (312 + 154*n + 71*n^2 + 14*n^3 + n^4) / 24 for n>1 and odd.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A206267.

Sequence in context: A217276 A076772 A248527 * A302457 A063470 A089715

Adjacent sequences:  A206259 A206260 A206261 * A206263 A206264 A206265

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 05 2012

STATUS

approved

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Last modified September 19 23:57 EDT 2020. Contains 337204 sequences. (Running on oeis4.)