A262760 Number of (3+2)X(n+2) 0..1 arrays with each row divisible by 5 and each column divisible by 7, read as a binary number with top and left being the most significant bits.

5, 25, 49, 129, 709, 4953, 16705, 73345, 384485, 2252185, 9821425, 47556225, 241769125, 1278440025, 6106506625, 30240858625, 152043549125, 774590745625, 3814859880625, 19015880330625, 95252710613125, 479215784705625

Offset

1,1

Comments

Row 3 of A262759.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +290*a(n-4) -1450*a(n-5) -19200*a(n-8) +96000*a(n-9) +370750*a(n-12) -1853750*a(n-13) -1409375*a(n-16) +7046875*a(n-17)

Example

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

Crossrefs

Cf. A262759.

Sequence in context: A147176 A298041 A074493 * A290700 A136914 A136913

Adjacent sequences: A262757 A262758 A262759 * A262761 A262762 A262763

Keyword

nonn

Author

R. H. Hardin, Sep 30 2015

Status

approved