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 A282718 #27 Nov 01 2024 12:41:08 %S A282718 0,1,3,4,7,13,24,44,81,149,274,504,927,1705,3136,5768,10609,19513, %T A282718 35890,66012,121415,223317,410744,755476,1389537,2555757,4700770, %U A282718 8646064,15902591,29249425,53798080,98950096,181997601,334745777,615693474 %N A282718 Satisfies the tribonacci recurrence: a(n) = a(n-1) + a(n-2) + a(n-3). %H A282718 Vincenzo Librandi, <a href="/A282718/b282718.txt">Table of n, a(n) for n = 0..1000</a> %H A282718 Julien Leroy, Michel Rigo, and Manon Stipulanti, <a href="http://dx.doi.org/10.1016/j.disc.2017.01.003">Counting the number of non-zero coefficients in rows of generalized Pascal triangles</a> Discrete Mathematics 340 (2017), 862-881. See Example 43. %H A282718 Dominika Závacká, Cristina Dalfó, and Miquel Angel Fiol, <a href="https://ceur-ws.org/Vol-3792/paper19.pdf">Integer sequences from k-iterated line digraphs</a>, CEUR: Proc. 24th Conf. Info. Tech. - Appl. and Theory (ITAT 2024) Vol 3792, 156-161. See p. 161, Table 2. %H A282718 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,1). %F A282718 a(n) = A000073(n+2), n >= 3. - _R. J. Mathar_, Mar 03 2017 %F A282718 G.f.: x*(1 + 2*x - x^3 - x^4)/(1 - x - x^2 - x^3). - _Bruno Berselli_, Mar 03 2017 %t A282718 Join[{0, 1, 3}, LinearRecurrence[{1, 1, 1}, {4, 7, 13}, 20]] (* _Vincenzo Librandi_, Mar 28 2017 *) %o A282718 (Magma) I:=[0,1,3,4,7,13]; [n le 6 select I[n] else Self(n-1)+Self(n-2)+Self(n-3): n in [1..40]]; // _Vincenzo Librandi_, Mar 28 2017 %Y A282718 Cf. A000073. %K A282718 nonn,easy %O A282718 0,3 %A A282718 _N. J. A. Sloane_, Mar 02 2017