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 A079675 #25 Oct 12 2022 09:34:39
%S A079675 1,1,6,26,106,431,1757,7168,29244,119305,486716,1985603,8100456,
%T A079675 33046585,134816705,549997641,2243767969,9153665985,37343255690,
%U A079675 152345382480,621507555626,2535499503900,10343812679475,42198572937400
%N A079675 a(1)=1; a(n)=sum(u=1,n-1,sum(v=1,u,sum(w=1,v,sum(x=1, w,sum(y=1,x,a(y)))))).
%C A079675 Row sums of Riordan array (1,1/(1-x)^5). A quintisection of A003520. - _Paul Barry_, Feb 02 2006
%H A079675 Michael De Vlieger, <a href="/A079675/b079675.txt">Table of n, a(n) for n = 1..1639</a>
%H A079675 D. Birmajer, J. B. Gil, and M. D. Weiner, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Gil/gil6.html">On the Enumeration of Restricted Words over a Finite Alphabet</a>, J. Int. Seq. 19 (2016) # 16.1.3, example 16.
%H A079675 Milan Janjić, <a href="https://www.emis.de/journals/JIS/VOL21/Janjic2/janjic103.html">Pascal Matrices and Restricted Words</a>, J. Int. Seq., Vol. 21 (2018), Article 18.5.2.
%H A079675 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (6,-10,10,-5,1).
%F A079675 a(1)=1, a(2)=1, a(3)=6, a(4)=26, a(5)=106, a(6)=431; for n>=7, a(n)=5*u(n-1)-4*u(n-2)+u(n-3)+b(n) where b(n) is the 6 periodic sequence (0, 1, 1, 0, -1, -1)
%F A079675 G.f.: (1-x)^5/((1-x)^5-x); a(n)=sum{k=0..n, binomial(5n-4k-1,k)}; - _Paul Barry_, Feb 02 2006
%t A079675 LinearRecurrence[{6,-10,10,-5,1},{1,1,6,26,106,431},40] (* _Harvey P. Dale_, Aug 21 2017 *)
%Y A079675 Cf. A055991, A052529, A001906.
%K A079675 nonn,easy
%O A079675 1,3
%A A079675 _Benoit Cloitre_, Jan 26 2003