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

%I #8 Mar 20 2018 20:36:34

%S 1,3,9,17,37,107,321,865,2449,7299,21897,64625,192277,576299,1728897,

%T 5174977,15507361,46516227,139548681,418517201,1255358341,3766010603,

%U 11298031809,33892678177,101675908657,305027017347,915081052041

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

%C Column 2 of A262472.

%H R. H. Hardin, <a href="/A262466/b262466.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) - 4*a(n-2) + 4*a(n-3) + 8*a(n-4) - 44*a(n-5) + 44*a(n-6) - 44*a(n-7) + 33*a(n-8).

%F Empirical g.f.: x*(1 - x + x^2 - 11*x^3 - 15*x^4 + 11*x^5 - 11*x^6 + 33*x^7) / ((1 - x)*(1 - 3*x)*(1 + x^2)*(1 - 11*x^4)). - _Colin Barker_, Mar 20 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Cf. A262472.

%K nonn

%O 1,2

%A _R. H. Hardin_, Sep 23 2015