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.
%I A251429 #8 Nov 29 2018 10:37:40 %S A251429 12,41,116,237,432,725,1128,1641,2316,3145,4148,5357,6776,8413,10328, %T A251429 12489,14924,17689,20764,24149,27928,32061,36568,41513,46868,52641, %U A251429 58924,65653,72856,80621,88896,97681,107092,117057,127596,138805,150624,163061 %N A251429 Number of length 2+2 0..n arrays with the sum of the maximum minus twice the median plus the minimum of adjacent triples multiplied by some arrangement of +-1 equal to zero. %H A251429 R. H. Hardin, <a href="/A251429/b251429.txt">Table of n, a(n) for n = 1..210</a> %F A251429 Empirical: a(n) = a(n-1) + 2*a(n-3) - a(n-4) - a(n-5) - a(n-6) - a(n-7) + 2*a(n-8) + a(n-10) - a(n-11). %F A251429 Empirical for n mod 12 = 0: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + 1 %F A251429 Empirical for n mod 12 = 1: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (97/54) %F A251429 Empirical for n mod 12 = 2: a(n) = (79/27)*n^3 + (29/18)*n^2 + (43/9)*n + (43/27) %F A251429 Empirical for n mod 12 = 3: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (11/2) %F A251429 Empirical for n mod 12 = 4: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (35/27) %F A251429 Empirical for n mod 12 = 5: a(n) = (79/27)*n^3 + (29/18)*n^2 + (43/9)*n + (113/54) %F A251429 Empirical for n mod 12 = 6: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + 1 %F A251429 Empirical for n mod 12 = 7: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (313/54) %F A251429 Empirical for n mod 12 = 8: a(n) = (79/27)*n^3 + (29/18)*n^2 + (43/9)*n + (43/27) %F A251429 Empirical for n mod 12 = 9: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (3/2) %F A251429 Empirical for n mod 12 = 10: a(n) = (79/27)*n^3 + (29/18)*n^2 + (17/3)*n + (35/27) %F A251429 Empirical for n mod 12 = 11: a(n) = (79/27)*n^3 + (29/18)*n^2 + (43/9)*n + (329/54) %F A251429 Empirical g.f.: x*(12 + 29*x + 75*x^2 + 97*x^3 + 125*x^4 + 114*x^5 + 98*x^6 + 55*x^7 + 27*x^8 + x^9 - x^10) / ((1 - x)^4*(1 + x)*(1 + x^2)*(1 + x + x^2)^2). - _Colin Barker_, Nov 29 2018 %e A251429 Some solutions for n=10: %e A251429 ..1....1....5....1....6....1....1....0....5....4....8....2....7....8....0....6 %e A251429 ..7....8...10....7....4....6....3....3....6....6....3....6....2....6....6....7 %e A251429 .10....3....7....3....3...10....5....1....3....7....9....5...10....6....2....1 %e A251429 ..7....7....8....9....6....1....1....4....5....4....1....9....7....8....5....9 %Y A251429 Row 2 of A251428. %K A251429 nonn %O A251429 1,1 %A A251429 _R. H. Hardin_, Dec 02 2014