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 A086817 #7 Oct 02 2018 16:37:23
%S A086817 3,9,22,48,102,182,328,566,910,1396,2025,2882,3976,5304,7002,9071,
%T A086817 11475,14444,17886,21896,26531,31880,37947,44899,52657,61500,71406,
%U A086817 82383,94592,108097,123017,139401,157439,177134,198634,221962,247378,274767,304483,336533,371083,408168,447944,490614,536208
%N A086817 a(n) is the number of terms in the expansion of (x+y-z)*(x^2+y^2-z^2)*(x^3+y^3-z^3)*...*(x^n+y^n-z^n).
%p A086817 P:= 1;
%p A086817 for n from 1 to 90 do
%p A086817 P:= expand(P*(x^n+y^n-z^n));
%p A086817 A[n]:= nops(P);
%p A086817 od:
%p A086817 seq(A[n],n=1..90); # _Robert Israel_, Apr 14 2017
%t A086817 Table[Length[Expand[Times@@Table[x^n+y^n-z^n,{n,i}]]],{i,50}] (* _Harvey P. Dale_, Oct 02 2018 *)
%Y A086817 Cf. A086796.
%K A086817 nonn
%O A086817 1,1
%A A086817 Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 06 2003
%E A086817 a(12)-a(45) from _Robert Israel_, Apr 14 2017