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 A036406 #30 Sep 08 2022 08:44:52 %S A036406 0,1,1,2,2,4,5,7,8,11,13,16,18,22,25,29,32,37,41,46,50,56,61,67,72,79, %T A036406 85,92,98,106,113,121,128,137,145,154,162,172,181,191,200,211,221,232, %U A036406 242,254,265,277,288,301,313,326,338,352,365,379,392 %N A036406 a(n) = ceiling(n^2/8). %H A036406 Vincenzo Librandi, <a href="/A036406/b036406.txt">Table of n, a(n) for n = 0..10000</a> %H A036406 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,0,1,-2,1) %F A036406 a(n) = (1/16)*(2n^2 + 9 - 5(-1)^n - 2(-1)^floor(n/2) + 2(-1)^floor((n-1)/2)). - _Ralf Stephan_, Jun 10 2005 %F A036406 G.f.: -x*(1-x-x^3+x^2+x^4) / ( (1+x)*(1+x^2)*(x-1)^3 ). - _R. J. Mathar_, Jan 22 2011 %F A036406 a(n) = 2*a(n-1) - a(n-2) + a(n-4) - 2*a(n-5) + a(n-6); a(0)=0, a(1)=1, a(2)=1, a(3)=2, a(4)=2, a(5)=4. - _Harvey P. Dale_, Jun 21 2011 %p A036406 A036406:=n->ceil(n^2/8); seq(A036406(n), n=0..60); # _Wesley Ivan Hurt_, Feb 14 2014 %t A036406 Ceiling[Range[0,60]^2/8] (* or *) LinearRecurrence[{2,-1,0,1,-2,1},{0,1,1,2,2,4},60] (* _Harvey P. Dale_, Jun 21 2011 *) %o A036406 (Magma) [Ceiling(n^2/8):n in [0..60]]; // _Vincenzo Librandi_, Oct 21 2011 %o A036406 (PARI) a(n)=ceil(n^2/8) \\ _Charles R Greathouse IV_, Feb 14 2014 %K A036406 nonn,easy %O A036406 0,4 %A A036406 _N. J. A. Sloane_