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A206264 Number of (n+1) X 6 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
72, 93, 218, 471, 932, 1725, 3011, 5014, 8016, 12385, 18572, 27141, 38768, 54273, 74621, 100956, 134604, 177109, 230238, 296019, 376748, 475029, 593783, 736290, 906200, 1107577, 1344912, 1623169, 1947800, 2324793, 2760689, 3262632, 3838388 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A206267.

LINKS

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

FORMULA

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

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

G.f.: x*(72 - 339*x + 668*x^2 - 543*x^3 - 144*x^4 + 683*x^5 - 591*x^6 + 232*x^7 - 36*x^8) / ((1 - x)^7*(1 + x)).

a(n) = (11520 + 8028*n + 5104*n^2 + 1665*n^3 + 295*n^4 + 27*n^5 + n^6) / 720 for n>1 and even.

a(n) = (10800 + 8028*n + 5104*n^2 + 1665*n^3 + 295*n^4 + 27*n^5 + n^6) / 720 for n>1 and odd.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A206267.

Sequence in context: A043967 A248970 A066943 * A063922 A063923 A030025

Adjacent sequences:  A206261 A206262 A206263 * A206265 A206266 A206267

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 05 2012

STATUS

approved

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Last modified August 6 08:46 EDT 2020. Contains 336228 sequences. (Running on oeis4.)