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%I #9 Oct 02 2023 16:22:26
%S 7,28,112,462,1904,7868,32531,134517,556259,2300219,9511719,39332200,
%T 162643507,672550879,2781080236,11500107101,47554350602,196643061212,
%U 813143132135,3362446402726,13904127534002,57495269615906
%N Number of 0..6 arrays x(0..n-1) of n elements with each no smaller than the sum of its two previous neighbors modulo 7.
%H R. H. Hardin, <a href="/A207098/b207098.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +3*a(n-2) -9*a(n-3) -8*a(n-4) +12*a(n-5) +11*a(n-6) -6*a(n-7) +5*a(n-8) -2*a(n-9) -17*a(n-10) +3*a(n-11) -4*a(n-12) -4*a(n-13) +a(n-14) -2*a(n-15) +9*a(n-16) -12*a(n-17) -a(n-18) +10*a(n-19) -19*a(n-20) -9*a(n-21) +7*a(n-22) -4*a(n-23) -3*a(n-24) +4*a(n-25) +14*a(n-26) +5*a(n-28) +11*a(n-29) +a(n-30) -a(n-31) -a(n-32) +8*a(n-33) +2*a(n-34) -a(n-35) +5*a(n-36) -2*a(n-37) -2*a(n-38) -a(n-40) -3*a(n-42) -a(n-43) -a(n-44) -a(n-49).
%e Some solutions for n=5:
%e ..2....5....1....2....3....4....5....1....4....4....0....0....1....0....0....4
%e ..6....5....1....3....3....6....5....4....4....5....0....2....3....2....3....6
%e ..6....3....5....6....6....3....4....6....5....2....0....6....4....2....5....4
%e ..6....4....6....5....2....5....4....5....4....1....5....3....2....6....3....6
%e ..5....2....4....4....4....3....5....4....6....3....6....5....6....3....1....3
%Y Column 6 of A207100.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 15 2012
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