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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A228744 Number of arrays of the median of three adjacent elements of some length 9 0..n array.

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%I A228744 #15 Mar 17 2018 05:45:47
%S A228744 88,1071,6130,23627,71278,181885,410828,845517,1617004,2913955,
%T A228744 4999182,8228935,13075154,20150881,30239032,44324729,63631392,
%U A228744 89660791,124237258,169556259,228237526,303382949,398639428,518266885,667211636,851185323
%N A228744 Number of arrays of the median of three adjacent elements of some length 9 0..n array.
%C A228744 Row 7 of A228740.
%H A228744 R. H. Hardin, <a href="/A228744/b228744.txt">Table of n, a(n) for n = 1..210</a>
%F A228744 Empirical: a(n) = (5/126)*n^7 + (4/3)*n^6 + (829/90)*n^5 + (93/4)*n^4 + (509/18)*n^3 + (221/12)*n^2 + (453/70)*n + 1.
%F A228744 Conjectures from _Colin Barker_, Mar 16 2018: (Start)
%F A228744 G.f.: x*(88 + 367*x + 26*x^2 - 353*x^3 + 86*x^4 - 21*x^5 + 8*x^6 - x^7) / (1 - x)^8.
%F A228744 a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.
%F A228744 (End)
%e A228744 Some solutions for n=4:
%e A228744   2  4  0  4  3  2  0  4  1  2  3  1  4  2  1  1
%e A228744   3  1  1  3  0  3  1  2  1  2  2  2  4  2  1  2
%e A228744   2  4  4  2  1  0  1  4  4  3  2  4  0  3  0  3
%e A228744   2  0  2  1  0  0  0  4  3  3  0  4  4  4  4  3
%e A228744   2  2  4  2  0  0  0  4  4  4  2  3  2  4  4  4
%e A228744   0  1  4  2  0  2  1  4  3  4  0  2  4  0  4  2
%e A228744   1  1  4  2  2  4  4  1  0  2  1  2  2  0  4  4
%Y A228744 Cf. A228740.
%K A228744 nonn
%O A228744 1,1
%A A228744 _R. H. Hardin_, Sep 01 2013