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A207095 Number of 0..3 arrays x(0..n-1) of n elements with each no smaller than the sum of its two previous neighbors modulo 4 1

%I

%S 4,10,26,68,176,458,1193,3103,8069,20982,54556,141854,368847,959072,

%T 2493770,6484280,16860367,43840173,113992823,296403114,770704718,

%U 2003979505,5210729566,13548892363,35229708616,91603972925,238187830252

%N Number of 0..3 arrays x(0..n-1) of n elements with each no smaller than the sum of its two previous neighbors modulo 4

%C Column 3 of A207100

%H R. H. Hardin, <a href="/A207095/b207095.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) -a(n-2) +a(n-3) -3*a(n-4) +a(n-6) -2*a(n-9) +2*a(n-12) +a(n-13) -a(n-16)

%e Some solutions for n=5

%e ..0....2....2....0....2....0....1....2....0....1....2....0....1....0....1....3

%e ..2....3....2....0....3....1....1....3....1....2....2....2....1....0....2....3

%e ..3....1....3....0....2....3....2....3....2....3....2....3....3....3....3....2

%e ..2....3....1....1....3....2....3....3....3....2....3....2....2....3....2....3

%e ..3....2....2....1....1....3....2....2....1....2....3....1....2....3....3....3

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 15 2012

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Last modified January 26 01:18 EST 2021. Contains 340427 sequences. (Running on oeis4.)