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 A304659 #30 Sep 08 2022 08:46:21
%S A304659 0,5,31,94,210,395,665,1036,1524,2145,2915,3850,4966,6279,7805,9560,
%T A304659 11560,13821,16359,19190,22330,25795,29601,33764,38300,43225,48555,
%U A304659 54306,60494,67135,74245,81840,89936,98549,107695,117390,127650,138491,149929,161980,174660,187985
%N A304659 a(n) = n*(n + 1)*(16*n - 1)/6.
%H A304659 Colin Barker, <a href="/A304659/b304659.txt">Table of n, a(n) for n = 0..1000</a>
%H A304659 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A304659 O.g.f.: x*(5 + 11*x)/(1 - x)^4.
%F A304659 E.g.f.: x*(30 + 63*x + 16*x^2)*exp(x)/6.
%F A304659 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).
%F A304659 a(n) + a(-n) = A033429(n).
%F A304659 a(n) = n*A007742(n) - Sum_{k = 0..n-1} A007742(k) for n > 0.
%F A304659 Also, this sequence is related to A076455 by the same type of recurrence:
%F A304659 A076455(n) = n*a(n) - Sum_{k = 0..n-1} a(k) for n > 0.
%t A304659 Table[n (n + 1) (16 n - 1)/6, {n, 0, 50}]
%o A304659 (Magma) [n*(n+1)*(16*n-1)/6: n in [0..41]]; // _Vincenzo Librandi_, May 23 2018
%o A304659 (PARI) concat(0, Vec(x*(5 + 11*x) / (1 - x)^4 + O(x^40))) \\ _Colin Barker_, May 25 2018
%Y A304659 Cf. A007742, A076455, A139273 (first differences).
%Y A304659 First lower diagonal of the rectangular array in A213835.
%K A304659 nonn,easy
%O A304659 0,2
%A A304659 _Bruno Berselli_, May 22 2018