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 A076458 #16 Jul 05 2025 08:58:26
%S A076458 17,165,678,1910,4335,8547,15260,25308,39645,59345,85602,119730,
%T A076458 163163,217455,284280,365432,462825,578493,714590,873390,1057287,
%U A076458 1268795,1510548,1785300,2095925,2445417,2836890,3273578,3758835,4296135,4889072,5541360
%N A076458 Sum of numbers that can be written as t*n + u*(n+1) for nonnegative integers t,u in exactly five ways.
%D A076458 Fred. Schuh, Vragen betreffende een onbepaalde vergelijking, Nieuw Tijdschrift voor Wiskunde, 52 (1964-1965) 193-198.
%H A076458 Vincenzo Librandi, <a href="/A076458/b076458.txt">Table of n, a(n) for n = 1..1000</a>
%H A076458 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A076458 a(n) = n*(n+1)*(10*n^2+8*n-1)/2.
%F A076458 G.f.: x*(17+80*x+23*x^2)/(1-x)^5.
%p A076458 seq(1/2*n*(n+1)*(10*n^2+8*n-1),n=1..40);
%t A076458 CoefficientList[Series[(17 + 80 x + 23 x^2)/(1 - x)^5, {x, 0, 50}], x] (* _Vincenzo Librandi_, Dec 30 2013 *)
%o A076458 (Magma) [n*(n+1)*(10*n^2+8*n-1)/2: n in [1..50]]; // _Vincenzo Librandi_, Dec 30 2013
%Y A076458 Cf. A002417, A076454-A076459.
%K A076458 easy,nonn
%O A076458 1,1
%A A076458 _Floor van Lamoen_, Oct 13 2002
%E A076458 More terms from _Vincenzo Librandi_, Dec 30 2013