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 A153796 #22 Dec 17 2023 16:20:37
%S A153796 0,6,48,126,240,390,576,798,1056,1350,1680,2046,2448,2886,3360,3870,
%T A153796 4416,4998,5616,6270,6960,7686,8448,9246,10080,10950,11856,12798,
%U A153796 13776,14790,15840,16926,18048,19206,20400,21630,22896,24198,25536,26910,28320,29766
%N A153796 6 times octagonal numbers: a(n) = 6*n*(3*n-2).
%H A153796 G. C. Greubel, <a href="/A153796/b153796.txt">Table of n, a(n) for n = 0..1000</a>
%H A153796 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A153796 a(n) = 18*n^2 - 12*n = 6*A000567(n) = 3*A139267(n) = 2*A152751(n).
%F A153796 a(n) = a(n-1) + 36*n - 30 (with a(0)=0). - _Vincenzo Librandi_, Dec 15 2010
%F A153796 From _G. C. Greubel_, Aug 29 2016: (Start)
%F A153796 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>2.
%F A153796 G.f.: 6*x*(1 + 5*x)/(1 - x)^3.
%F A153796 E.g.f.: 6*x*(1 + 3*x)*exp(x). (End)
%p A153796 A153796:=n->6*n*(3*n-2): seq(A153796(n), n=0..60); # _Wesley Ivan Hurt_, Aug 29 2016
%t A153796 s=0;lst={s};Do[s+=n;AppendTo[lst,s],{n,6,8!,36}];lst (* _Vladimir Joseph Stephan Orlovsky_, Apr 03 2009 *)
%t A153796 Table[6*n*(3*n-2), {n,0,25}] (* or *) LinearRecurrence[{3,-3,1}, {0,6,48}, 25] (* _G. C. Greubel_, Aug 29 2016 *)
%t A153796 6*PolygonalNumber[8,Range[0,50]] (* _Harvey P. Dale_, Dec 17 2023 *)
%o A153796 (Magma) [6*n*(3*n-2): n in [0..60]]; // _Wesley Ivan Hurt_, Aug 29 2016
%o A153796 (PARI) a(n)=6*n*(3*n-2) \\ _Charles R Greathouse IV_, Aug 29 2016
%Y A153796 Cf. A000567, A139267, A152751.
%K A153796 easy,nonn
%O A153796 0,2
%A A153796 _Omar E. Pol_, Jan 19 2009