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 A369850 #17 Mar 15 2024 07:25:10
%S A369850 0,1,3,6,10,16,29,64,156,376,860,1873,3965,8347,17751,38303,83488,
%T A369850 182497,397978,864339,1871236,4046070,8751965,18952107,41080980,
%U A369850 89090436,193201660,418857277,907802332,1967174726,4262706876,9237582992,20020241409,43391549313
%N A369850 Number of compositions of 5*n-2 into parts 4 and 5.
%H A369850 Paolo Xausa, <a href="/A369850/b369850.txt">Table of n, a(n) for n = 1..1000</a>
%H A369850 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-4,1).
%F A369850 a(n) = A017827(5*n-2).
%F A369850 a(n) = Sum_{k=0..floor(n/4)} binomial(n+k,n-2-4*k).
%F A369850 a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 4*a(n-4) + a(n-5).
%F A369850 G.f.: x^2*(1-x)^2/((1-x)^5 - x^4).
%t A369850 LinearRecurrence[{5, -10, 10, -4, 1}, {0, 1, 3, 6, 10}, 50] (* _Paolo Xausa_, Mar 15 2024 *)
%o A369850 (PARI) a(n) = sum(k=0, n\4, binomial(n+k, n-2-4*k));
%Y A369850 Cf. A099131, A368475, A369849, A369851.
%Y A369850 Cf. A017827.
%K A369850 nonn,easy
%O A369850 1,3
%A A369850 _Seiichi Manyama_, Feb 03 2024