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 A188050 #23 Sep 08 2022 08:45:56
%S A188050 0,20,100,280,600,1100,1820,2800,4080,5700,7700,10120,13000,16380,
%T A188050 20300,24800,29920,35700,42180,49400,57400,66220,75900,86480,98000,
%U A188050 110500,124020,138600,154280,171100,189100,208320,228800,250580,273700
%N A188050 a(n) = A016755(n) - A001845(n).
%C A188050 A016755 are odd cubes and A001845 are centered octahedral numbers, so the sequence might be regarded as odd cubes without their octahedral content.
%C A188050 A000330 are square pyramidal numbers.
%H A188050 Vincenzo Librandi, <a href="/A188050/b188050.txt">Table of n, a(n) for n = 0..10000</a>
%H A188050 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A188050 a(n) = (10/3)*n*(n + 1)*(2*n + 1).
%F A188050 a(n) = 20 * A000330(n).
%F A188050 G.f.: 20*x*(1+x)/(1-x)^4. - _Klaus Brockhaus_, Mar 20 2011
%p A188050 (10/3)*n*(n+1)*(2*n+1)
%t A188050 10n(n+1)(2n+1)/3
%t A188050 LinearRecurrence[{4,-6,4,-1},{0,20,100,280},40] (* _Harvey P. Dale_, Jul 18 2016 *)
%o A188050 (Magma) A016755:=func< n | (2*n+1)^3 >; A001845:=func< n | (2*n+1)*(2*n^2+2*n+3)/3 >; [ A016755(n)-A001845(n): n in [0..40] ]; // _Klaus Brockhaus_, Mar 20 2011
%Y A188050 Cf. A016755, A001845, A000330.
%K A188050 nonn,easy
%O A188050 0,2
%A A188050 _Damien Pras_, Mar 19 2011