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A263119 Number of (n+3) X (1+3) 0..1 arrays with each row divisible by 15 and column not divisible by 15, read as a binary number with top and left being the most significant bits. 1

%I

%S 14,29,59,119,238,477,955,1911,3822,7645,15291,30583,61166,122333,

%T 244667,489335,978670,1957341,3914683,7829367,15658734,31317469,

%U 62634939,125269879,250539758,501079517,1002159035,2004318071,4008636142

%N Number of (n+3) X (1+3) 0..1 arrays with each row divisible by 15 and column not divisible by 15, read as a binary number with top and left being the most significant bits.

%H R. H. Hardin, <a href="/A263119/b263119.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + a(n-4) - 2*a(n-5) = A265381(n+2).

%F Empirical g.f.: x*(14 + x + x^2 + x^3 - 14*x^4) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + x^2)). - _Colin Barker_, Jan 01 2019

%e Some solutions for n=4:

%e ..0..0..0..0....1..1..1..1....0..0..0..0....0..0..0..0....0..0..0..0

%e ..0..0..0..0....1..1..1..1....1..1..1..1....0..0..0..0....0..0..0..0

%e ..0..0..0..0....1..1..1..1....1..1..1..1....1..1..1..1....1..1..1..1

%e ..0..0..0..0....0..0..0..0....1..1..1..1....0..0..0..0....0..0..0..0

%e ..1..1..1..1....0..0..0..0....0..0..0..0....0..0..0..0....1..1..1..1

%e ..0..0..0..0....1..1..1..1....1..1..1..1....0..0..0..0....1..1..1..1

%e ..0..0..0..0....1..1..1..1....0..0..0..0....1..1..1..1....0..0..0..0

%Y Column 1 of A263124.

%K nonn

%O 1,1

%A _R. H. Hardin_, Oct 10 2015

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Last modified September 28 16:40 EDT 2020. Contains 337393 sequences. (Running on oeis4.)