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 A270869 #14 Sep 08 2022 08:46:16
%S A270869 3,69,345,1203,3351,7953,16749,32175,57483,96861,155553,239979,357855,
%T A270869 518313,732021,1011303,1370259,1824885,2393193,3095331,3953703,
%U A270869 4993089,6240765,7726623,9483291,11546253,13953969,16747995,19973103,23677401,27912453
%N A270869 a(n) = n^5 + 4*n^4 + 13*n^3 + 23*n^2 + 25*n + 3.
%H A270869 Vincenzo Librandi, <a href="/A270869/b270869.txt">Table of n, a(n) for n = 0..1000</a>
%H A270869 Andrew Misseldine, <a href="http://arxiv.org/abs/1508.03757">Counting Schur Rings over Cyclic Groups</a>, arXiv preprint arXiv:1508.03757 [math.RA], 2015. (page 19, 4th row; page 21, 5th row).
%H A270869 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-15,20,-15,6,-1).
%F A270869 O.g.f.: (3 + 51*x - 24*x^2 + 108*x^3 - 27*x^4 + 9*x^5)/(1-x)^6.
%F A270869 E.g.f.: (3 + 66*x + 105*x^2 + 62*x^3 + 14*x^4 + x^5)*exp(x).
%F A270869 a(n) = 6*a(n-1) -15*a(n-2) +20*a(n-3) -15*a(n-4) +6*a(n-5) -a(n-6).
%t A270869 Table[n^5 + 4 n^4 + 13 n^3 + 23 n^2 + 25 n + 3, {n, 0, 40}]
%o A270869 (Magma) [n^5+4*n^4+13*n^3+23*n^2+25*n+3: n in [0..40]];
%o A270869 (PARI) x='x+O('x^99); Vec((3+51*x-24*x^2+108*x^3-27*x^4+9*x^5)/(1-x)^6) \\ _Altug Alkan_, Apr 03 2016
%Y A270869 Cf. A270867, A270868.
%K A270869 nonn,easy
%O A270869 0,1
%A A270869 _Vincenzo Librandi_, Apr 03 2016