A262845 Number of (n+2)X(3+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.

12, 196, 1336, 5184, 31512, 175820, 793812, 4140908, 21744992, 104726376, 525986400, 2691397140, 13304013852, 66260714708, 334758471368, 1670112463824, 8315216847336, 41755671803804, 208872540829092, 1041336962146684

Offset

1,1

Comments

Column 3 of A262849.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +203*a(n-3) -1015*a(n-4) -17262*a(n-6) +86310*a(n-7) +803306*a(n-9) -4016530*a(n-10) -22920723*a(n-12) +114603615*a(n-13) +424713065*a(n-15) -2123565325*a(n-16) -5289109868*a(n-18) +26445549340*a(n-19) +45727616604*a(n-21) -228638083020*a(n-22) -289788580823*a(n-24) +1448942904115*a(n-25) +1453125527917*a(n-27) -7265627639585*a(n-28) -5836364956590*a(n-30) +29181824782950*a(n-31) +16212555187738*a(n-33) -81062775938690*a(n-34) -21276199455861*a(n-36) +106380997279305*a(n-37) -6355957095425*a(n-39) +31779785477125*a(n-40) +38763541794536*a(n-42) -193817708972680*a(n-43)

Example

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

Crossrefs

Cf. A262849.

Sequence in context: A159498 A034671 A066230 * A358363 A321033 A048667

Adjacent sequences: A262842 A262843 A262844 * A262846 A262847 A262848

Keyword

nonn

Author

R. H. Hardin, Oct 03 2015

Status

approved