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 A056015 #36 Mar 19 2024 21:40:30 %S A056015 0,0,0,0,0,1,6,31,152,730,3480,16542,78544,372779,1768958,8393741, %T A056015 39827472,188975588,896658432,4254492236,20186832928,95783024581, %U A056015 454473817254,2156399264651,10231739547432,48547824776670,230350985294584,1092975362559562 %N A056015 a(n) = 6*a(n-1) - 5*a(n-2) - 4*a(n-3) - 3*a(n-4) + 2*a(n-5) + a(n-6), with a(0)=...=a(4)=0, a(5)=1. %C A056015 With a(0)=0, a(1)=1, a(2)=1, a(3)=2, a(4)=4, a(5)=7, this recurrence produces a(n) = A000073(n+1) (tribonacci numbers). %H A056015 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-5,-4,-3,2,1). %F A056015 O.g.f.: -x^5/((x^3+x^2-5*x+1)*(x^3+x^2+x-1)). - _R. J. Mathar_, Nov 23 2007 %Y A056015 Cf. A000073, A056014. %K A056015 nonn,easy %O A056015 0,7 %A A056015 _Asher Auel_, Jun 06 2000 %E A056015 New name, from formula, added by _Michel Marcus_, Mar 19 2024