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 A006009 M3513 #40 Feb 07 2024 11:55:48
%S A006009 4,16,48,108,216,384,640,1000,1500,2160,3024,4116,5488,7168,9216,
%T A006009 11664,14580,18000,22000,26620,31944,38016,44928,52728,61516,71344,
%U A006009 82320,94500,108000,122880,139264,157216,176868,198288,221616,246924,274360,304000,336000
%N A006009 Number of paraffins.
%D A006009 S. M. Losanitsch, Die Isomerie-Arten bei den Homologen der Paraffin-Reihe, Chem. Ber. 30 (1897), 1917-1926.
%D A006009 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A006009 Alois P. Heinz, <a href="/A006009/b006009.txt">Table of n, a(n) for n = 1..1000</a>
%H A006009 S. M. Losanitsch, <a href="/A000602/a000602_1.pdf">Die Isomerie-Arten bei den Homologen der Paraffin-Reihe</a>, Chem. Ber. 30 (1897), 1917-1926. (Annotated scanned copy)
%H A006009 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (3,-1,-5,5,1,-3,1).
%F A006009 a(n) = 2*(A005994(n) + binomial(n, 4)).
%F A006009 G.f.: 4*x*(1-x^3) / ((1-x)^4*(1-x^2)^2). - _Alois P. Heinz_, Aug 13 2008
%F A006009 a(n) = Sum_{i=1..n} i*floor(i^2/2). - _Enrique Pérez Herrero_, Mar 10 2012
%p A006009 a:= n-> (Matrix([[0$4,4,16,48,108]]). Matrix(8, (i,j)-> if (i=j-1) then 1 elif j=1 then [4,-4,-4,10,-4,-4,4,-1][i] else 0 fi)^n)[1,1]: seq(a(n), n=1..40); # _Alois P. Heinz_, Aug 13 2008
%t A006009 a[n_] := 1/16*(2*n^4+12*n^3+24*n^2+2*(9-(-1)^n)*n-3*(-1)^n+3); Array[a, 40] (* _Jean-François Alcover_, Mar 17 2014 *)
%Y A006009 4*A007009.
%Y A006009 Cf. A005994, A005997.
%K A006009 nonn,easy
%O A006009 1,1
%A A006009 _N. J. A. Sloane_