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Number of 0..n arrays x(0..4) of 5 elements with each no smaller than the sum of its three previous neighbors modulo (n+1)
1

%I #5 Mar 31 2012 12:36:40

%S 12,46,175,406,938,1813,3414,5682,9412,14443,22009,31668,45374,62393,

%T 85516,113373,149874,193249,248539,312886,393096,485530,598634,727155,

%U 881972,1056600,1264221,1495936,1768186,2070552,2422168,2809532,3256044

%N Number of 0..n arrays x(0..4) of 5 elements with each no smaller than the sum of its three previous neighbors modulo (n+1)

%C Row 5 of A200668

%H R. H. Hardin, <a href="/A200669/b200669.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = -2*a(n-1) -2*a(n-2) +5*a(n-4) +8*a(n-5) +7*a(n-6) +2*a(n-7) -5*a(n-8) -8*a(n-9) -9*a(n-10) -10*a(n-11) -9*a(n-12) -6*a(n-13) +4*a(n-14) +16*a(n-15) +20*a(n-16) +16*a(n-17) +4*a(n-18) -6*a(n-19) -9*a(n-20) -10*a(n-21) -9*a(n-22) -8*a(n-23) -5*a(n-24) +2*a(n-25) +7*a(n-26) +8*a(n-27) +5*a(n-28) -2*a(n-30) -2*a(n-31) -a(n-32)

%e Some solutions for n=6

%e ..5....0....5....1....1....4....4....0....4....0....0....4....0....0....1....4

%e ..5....3....5....1....2....6....5....1....5....5....4....6....3....1....6....5

%e ..4....5....5....6....5....4....6....6....5....6....4....4....6....6....0....5

%e ..6....6....1....2....5....5....3....1....1....4....2....0....6....2....1....0

%e ..5....1....4....5....5....4....2....4....4....2....3....4....1....3....6....4

%K nonn

%O 1,1

%A _R. H. Hardin_ Nov 20 2011