A217838 Number of n element 0..1 arrays with each element the minimum of 7 adjacent elements of a random 0..1 array of n+6 elements.

2, 4, 7, 11, 16, 22, 29, 37, 47, 61, 82, 114, 162, 232, 331, 467, 650, 894, 1220, 1660, 2262, 3096, 4261, 5893, 8175, 11351, 15747, 21803, 30121, 41535, 57210, 78778, 108521, 149615, 206456, 285100, 393865, 544165, 751675, 1037963, 1432772

Offset

1,1

Comments

Column 7 of A217839.

Links

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

Formula

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

Empirical g.f.: x*(2 + x^2 + x^3 + x^4 + x^5 + x^6 + x^7) / ((1 - x + x^4)*(1 - x - x^4)). - Colin Barker, Jul 23 2018

Example

Some solutions for n=8:
..0....0....1....0....0....0....0....0....1....1....0....0....0....0....0....0
..1....1....0....0....0....1....0....0....1....1....0....0....0....0....1....0
..1....1....0....0....1....1....0....1....0....1....1....0....0....0....1....0
..1....1....0....1....0....1....1....1....0....1....1....0....0....1....1....0
..1....1....0....1....0....1....1....0....0....1....1....0....1....1....0....0
..1....1....0....1....0....0....1....0....0....1....0....0....1....0....0....0
..1....0....0....1....0....0....1....0....0....0....0....0....1....0....0....1
..1....0....0....0....0....0....1....0....0....0....0....0....0....0....0....0

Crossrefs

Cf. A217839.

Sequence in context: A152947 A212369 A212368 * A212367 A225088 A175777

Adjacent sequences: A217835 A217836 A217837 * A217839 A217840 A217841

Keyword

nonn

Author

R. H. Hardin, Oct 12 2012

Status

approved