A262850 Number of (1+2)X(n+2) 0..1 arrays with each row divisible by 7 and column not divisible by 7, read as a binary number with top and left being the most significant bits.

6, 6, 12, 318, 900, 4536, 34782, 178926, 1042284, 6538206, 38160540, 227814120, 1377960126, 8227422006, 49321272972, 296370593598, 1776644188020, 10658199015576, 63967089528222, 383739633130686, 2302372435469484

Offset

1,1

Comments

Row 1 of A262849.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +72*a(n-3) -432*a(n-4) -1270*a(n-6) +7620*a(n-7) -2880*a(n-9) +17280*a(n-10) +113591*a(n-12) -681546*a(n-13) +115128*a(n-15) -690768*a(n-16)

Example

Some solutions for n=4
..1..0..1..0..1..0....1..1..1..0..0..0....1..0..1..0..1..0....0..1..0..1..0..1
..0..0..0..0..0..0....0..0..0..0..0..0....0..1..0..1..0..1....0..0..0..0..0..0
..1..1..1..1..1..1....0..0..0..1..1..1....0..1..1..1..0..0....1..1..1..1..1..1

Crossrefs

Cf. A262849.

Sequence in context: A315801 A352135 A272349 * A262849 A115014 A168332

Adjacent sequences: A262847 A262848 A262849 * A262851 A262852 A262853

Keyword

nonn

Author

R. H. Hardin, Oct 03 2015

Status

approved