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 A248016 #23 Nov 30 2016 22:12:33 %S A248016 0,0,3,16,67,204,546,1268,2714,5348,9965,17580,29781,48520,76660, %T A248016 117624,176196,257976,370503,522456,725175,991540,1337974,1782924, %U A248016 2349438,3063164,3955601,5061524,6423017,8086224,10106280,12543280,15468232,18958128,23103051,28000224,33762411,40510812,48384906,57534052 %N A248016 Sum over each antidiagonal of A248011. %H A248016 Christopher Hunt Gribble, <a href="/A248016/b248016.txt">Table of n, a(n) for n = 1..10000</a> %F A248016 Empirically, a(n) = (2*n^7 + 14*n^6 + 14*n^5 + 70*n^4 - 77*n^3 - 399*n^2 + 61*n + 105 - 105*(-1)^n - 35*n^3*(-1)^n - 105*n^2*(-1)^n + 35*n*(-1)^n)/6720. %F A248016 Empirical g.f.: -x^3*(x^2+1)*(x^4-6*x^2-4*x-3) / ((x-1)^8*(x+1)^4). - _Colin Barker_, Apr 06 2015 %e A248016 a(1..9) are formed as follows: %e A248016 . Antidiagonals of A248011 n a(n) %e A248016 . 0 1 0 %e A248016 . 0 0 2 0 %e A248016 . 1 1 1 3 3 %e A248016 . 2 6 6 2 4 16 %e A248016 . 6 14 27 14 6 5 67 %e A248016 . 10 32 60 60 32 10 6 204 %e A248016 . 19 55 129 140 129 55 19 7 546 %e A248016 . 28 94 218 294 294 218 94 28 8 1268 %e A248016 .44 140 363 506 608 506 363 140 44 9 2714 %p A248016 b := proc (n::integer, k::integer)::integer; %p A248016 (4*k^3*n^3 - 12*k^2*n^2 + 2*k^3 + 6*k^2*n + 6*k*n^2 + 2*n^3 - 12*k^2 + 11*k*n - 12*n^2 + 4*k + 4*n - 3 - (2*k^3 + 6*k^2*n - 12*k^2 + 3*k*n + 4*k - 3)*(-1)^n - (6*k*n^2 + 2*n^3 + 3*k*n - 12*n^2 + 4*n - 3)*(-1)^k + (3*k*n - 3)*(-1)^k*(-1)^n)/96; %p A248016 end proc; %p A248016 for j to 10000 do %p A248016 a := 0; %p A248016 for k from j by -1 to 1 do %p A248016 n := j-k+1; %p A248016 a := a+b(n, k) %p A248016 end do; %p A248016 printf("%d, ", a) %p A248016 end do; %Y A248016 Cf. A248011. %K A248016 nonn %O A248016 1,3 %A A248016 _Christopher Hunt Gribble_, Sep 29 2014 %E A248016 Terms corrected and extended by _Christopher Hunt Gribble_, Apr 02 2015