A262849 T(n,k)=Number of (n+2)X(k+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, 13, 12, 34, 27, 318, 196, 132, 54, 900, 3181, 1336, 396, 109, 4536, 31050, 37635, 5184, 1264, 219, 34782, 352880, 771084, 420654, 31512, 3962, 438, 178926, 4679725, 17912392, 14762016, 3896365, 175820, 11886, 877, 1042284, 58693450, 481968171

Offset

1,1

Comments

Table starts

....6......6.......12........318..........900..........4536.........34782

...13.....34......196.......3181........31050........352880.......4679725

...27....132.....1336......37635.......771084......17912392.....481968171

...54....396.....5184.....420654.....14762016.....661066920...35819485902

..109...1264....31512....3896365....290338650...26232879096.2864161217701

..219...3962...175820...39348387...5692555116.1007501698644

..438..11886...793812..417279054.108936025308

..877..35914..4140908.3999504445

.1755.108556.21744992

.3510.325668

Links

R. H. Hardin, Table of n, a(n) for n = 1..70

Formula

Empirical for column k:

k=1: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4)

k=2: [order 15]

k=3: [order 43]

k=4: [order 29]

Empirical for row n:

n=1: [linear recurrence of order 16]

Example

Some solutions for n=3 k=4
..0..1..1..1..0..0....0..0..0..1..1..1....0..0..1..1..1..0....0..0..0..0..0..0
..0..0..0..1..1..1....1..1..1..0..0..0....0..1..1..1..0..0....1..1..1..1..1..1
..0..0..1..1..1..0....0..1..0..1..0..1....1..1..0..0..0..1....1..0..0..0..1..1
..0..0..1..1..1..0....0..1..0..1..0..1....0..1..1..1..0..0....1..0..0..0..1..1
..1..1..1..1..1..1....0..1..0..1..0..1....1..1..1..0..0..0....1..0..0..0..1..1

Crossrefs

Column 1 is A033129(n+2).

Sequence in context: A352135 A272349 A262850 * A115014 A168332 A214828

Adjacent sequences: A262846 A262847 A262848 * A262850 A262851 A262852

Keyword

nonn,tabl

Author

R. H. Hardin, Oct 03 2015

Status

approved