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A250347 Number of length n arrays x(i), i=1..n with x(i) in i..i+4 and no value appearing more than 2 times.

%I A250347 #6 Jul 23 2025 12:19:43
%S A250347 5,25,122,581,2724,12734,59406,276816,1289208,6002949,27948445,
%T A250347 130114896,605739129,2819935996,13127753699,61113960653,284504996836,
%U A250347 1324460800690,6165782447251,28703656674418,133624541803551,622064214270768
%N A250347 Number of length n arrays x(i), i=1..n with x(i) in i..i+4 and no value appearing more than 2 times.
%C A250347 Column 4 of A250351
%H A250347 R. H. Hardin, <a href="/A250347/b250347.txt">Table of n, a(n) for n = 1..210</a>
%F A250347 Empirical: a(n) = 5*a(n-1) -4*a(n-3) -9*a(n-4) -36*a(n-5) +7*a(n-6) +23*a(n-7) +13*a(n-8) +2*a(n-9) -5*a(n-10) +a(n-12)
%e A250347 Some solutions for n=6
%e A250347 ..2....0....4....4....3....0....3....4....4....2....2....3....1....0....4....1
%e A250347 ..4....4....2....3....1....5....2....3....3....1....2....1....5....5....2....2
%e A250347 ..5....3....3....3....5....2....2....4....5....5....3....3....5....2....5....5
%e A250347 ..4....7....3....4....4....7....3....7....3....4....3....6....4....6....6....6
%e A250347 ..6....7....6....6....7....8....7....8....4....6....6....8....4....7....8....7
%e A250347 ..7....9....7....6....9....7....9....9....5....6....7....8....9....9....5....9
%K A250347 nonn
%O A250347 1,1
%A A250347 _R. H. Hardin_, Nov 19 2014