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 A033596 #15 Nov 20 2024 18:58:41
%S A033596 3,0,3,48,195,528,1155,2208,3843,6240,9603,14160,20163,27888,37635,
%T A033596 49728,64515,82368,103683,128880,158403,192720,232323,277728,329475,
%U A033596 388128,454275,528528,611523,703920,806403,919680,1044483,1181568,1331715,1495728,1674435
%N A033596 a(n) = (n^2 - 1)*(n^2 - 3).
%H A033596 G. C. Greubel, <a href="/A033596/b033596.txt">Table of n, a(n) for n = 0..1000</a>
%H A033596 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A033596 From _Wesley Ivan Hurt_, Oct 30 2014: (Start)
%F A033596 G.f.: 3*(1 -5*x +11*x^2 +x^3)/(1-x)^5.
%F A033596 a(n) = 5*a(n-1) -10*a(n-2) +10*a(n-3) -5*a(n-4) +a(n-5).
%F A033596 a(n) = (n^2-1)*(n^2-3) = (A000290(n)-1)*(A000290(n)-3) = A000583(n) - A082109(n+1). (End)
%F A033596 E.g.f.: (3 - 3*x + 3*x^2 + 6*x^3 + x^4)*exp(x). - _G. C. Greubel_, Mar 05 2020
%p A033596 A033596:=n->(n^2-1)*(n^2-3): seq(A033596(n), n=0..30); # _Wesley Ivan Hurt_, Oct 30 2014
%t A033596 Table[(n^2 - 1)*(n^2 - 3), {n, 0, 30}] (* or *)
%t A033596 CoefficientList[Series[3 (1 - 5 x + 11 x^2 + x^3)/(1 - x)^5, {x, 0, 30}], x] (* _Wesley Ivan Hurt_, Oct 30 2014 *)
%t A033596 LinearRecurrence[{5,-10,10,-5,1},{3,0,3,48,195},40] (* _Harvey P. Dale_, Nov 20 2024 *)
%o A033596 (Magma) [(n^2-1)*(n^2-3) : n in [0..30]]; // _Wesley Ivan Hurt_, Oct 30 2014
%o A033596 (PARI) vector(31, n, my(m=n-1); (m^2-1)*(m^2-3)) \\ _G. C. Greubel_, Mar 05 2020
%o A033596 (Sage) [(n^2-1)*(n^2-3) for n in (0..30)] # _G. C. Greubel_, Mar 05 2020
%Y A033596 Cf. A000290 (n^2), A000583 (n^4), A082109.
%K A033596 nonn,easy
%O A033596 0,1
%A A033596 _N. J. A. Sloane_