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A250365 Number of length 7 arrays x(i), i=1..7 with x(i) in i..i+n and no value appearing more than 3 times.

%I A250365 #6 Jul 23 2025 12:20:52
%S A250365 128,2187,16128,76300,272760,803382,2052904,4698744,9854280,19251970,
%T A250365 35471832,62220324,104664664,169827630,267047880,408510832,609855144,
%U A250365 890859834,1276217080,1796395740,2488600632,3397832614,4578054504
%N A250365 Number of length 7 arrays x(i), i=1..7 with x(i) in i..i+n and no value appearing more than 3 times.
%C A250365 Row 7 of A250361
%H A250365 R. H. Hardin, <a href="/A250365/b250365.txt">Table of n, a(n) for n = 1..210</a>
%F A250365 Empirical: a(n) = n^7 + 7*n^6 + 21*n^5 + 147*n^3 + 49*n^2 + 7*n for n>4
%e A250365 Some solutions for n=4
%e A250365 ..4....3....2....2....1....2....1....0....2....3....3....1....0....1....4....4
%e A250365 ..4....5....4....2....5....2....1....2....5....1....2....2....5....2....4....5
%e A250365 ..3....3....6....4....6....2....2....5....4....2....2....6....6....3....4....4
%e A250365 ..5....7....6....5....3....4....7....3....6....6....6....6....7....6....3....7
%e A250365 ..4....8....4....5....5....8....7....5....4....8....7....8....4....8....5....6
%e A250365 ..6....7....5....7....5....6....9....8....9....8....9....7....5....9....9....5
%e A250365 ..6....7....7....7....7....9....9....8....8...10....6...10...10....7....8....8
%K A250365 nonn
%O A250365 1,1
%A A250365 _R. H. Hardin_, Nov 19 2014