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Number of (1+2)X(n+2) 0..1 arrays with each row divisible by 5 and column not divisible by 5, read as a binary number with top and left being the most significant bits.
1

%I #8 Oct 02 2015 08:14:44

%S 0,36,76,344,2178,15556,82386,479148,2894976,17686548,104720692,

%T 626126744,3760257066,22609447684,135448403466,812343844524,

%U 4874677265880,29255734010196,175501301390140,1052950222812440

%N Number of (1+2)X(n+2) 0..1 arrays with each row divisible by 5 and column not divisible by 5, read as a binary number with top and left being the most significant bits.

%C Row 1 of A262795.

%H R. H. Hardin, <a href="/A262796/b262796.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -31*a(n-2) +117*a(n-3) +111*a(n-4) -3105*a(n-5) +11163*a(n-6) -44577*a(n-7) +54480*a(n-8) +312066*a(n-9) -1253202*a(n-10) +5661630*a(n-11) -10623030*a(n-12) -6302070*a(n-13) +44353650*a(n-14) -285745590*a(n-15) +608932635*a(n-16) -336973095*a(n-17) +17702745*a(n-18) +5906191005*a(n-19) -13283846169*a(n-20) +13243177431*a(n-21) -21990624909*a(n-22) -40461569577*a(n-23) +93075113494*a(n-24) -109367769060*a(n-25) +214864926232*a(n-26) +34835506992*a(n-27) -80389631520*a(n-28) +96467557824*a(n-29) -192935115648*a(n-30)

%e Some solutions for n=4

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

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

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

%Y Cf. A262795.

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 02 2015