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 A017830 #26 Jul 09 2025 14:14:32
%S A017830 1,0,0,0,1,1,1,1,2,2,3,4,6,7,9,12,17,22,29,38,51,67,89,118,157,207,
%T A017830 274,363,482,638,845,1119,1483,1964,2602,3447,4567,6049,8013,10615,
%U A017830 14063,18629,24678,32691,43307,57369
%N A017830 Expansion of 1/(1-x^4-x^5-x^6-x^7-x^8).
%C A017830 Number of compositions (ordered partitions) of n into parts 4, 5, 6, 7 and 8. - _Ilya Gutkovskiy_, May 25 2017
%H A017830 Vincenzo Librandi, <a href="/A017830/b017830.txt">Table of n, a(n) for n = 0..1000</a>
%H A017830 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,1,1,1,1,1).
%F A017830 a(0)=1, a(1)=0, a(2)=0, a(3)=0, a(4)=1, a(5)=1, a(6)=1, a(7)=1; for n>7, a(n) = a(n-4)+a(n-5)+a(n-6)+a(n-7)+a(n-8). [_Harvey P. Dale_, Aug 05 2011]
%t A017830 CoefficientList[Series[1/(1 - Total[x^Range[4, 8]]), {x, 0, 50}], x] (* or *) LinearRecurrence[{0, 0, 0, 1, 1, 1, 1, 1}, {1, 0, 0, 0, 1, 1, 1, 1}, 50] (* _Harvey P. Dale_, Aug 05 2011 *)
%o A017830 (Magma) I:=[1,0,0,0,1,1,1,1]; [n le 8 select I[n] else Self(n-4)+Self(n-5)+Self(n-6)+Self(n-7)+Self(n-8): n in [1..50]]; // _Vincenzo Librandi_, Jun 27 2013
%o A017830 (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x^4-x^5-x^6-x^7-x^8))); // _Vincenzo Librandi_, Jun 27 2013
%K A017830 nonn,easy
%O A017830 0,9
%A A017830 _N. J. A. Sloane_