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 A131579 #28 Jul 06 2025 12:49:25
%S A131579 0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,
%T A131579 2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,
%U A131579 4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2,5,8,1,4,7,0,3,6,9,2
%N A131579 Period 10: repeat 0, 3, 6, 9, 2, 5, 8, 1, 4, 7.
%C A131579 a(n) = last digit of 3*n, n >= 0. a(n+7) = last digit of 3*n + 1, n >= 0, and a(n+4) = last digit of 3*n + 2, n >= 0. The last digit of -3*n = A144468(n), n >= 0, the last one of -3*n + 1 = A144468(n+3), n >= 0 and the last one of -3*n + 2 = A144468(n+6), n >= 0. - _Wolfdieter Lang_, Aug 14 2017
%H A131579 Vincenzo Librandi, <a href="/A131579/b131579.txt">Table of n, a(n) for n = 0..1000</a>
%H A131579 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,1)
%F A131579 a(n) = A008585(n) mod 10. - _Bruno Berselli_, Mar 08 2011
%F A131579 G.f.: -x*(3 + 6*x + 9*x^2 + 2*x^3 + 5*x^4 + 8*x^5 + x^6 + 4*x^7 + 7*x^8) / ( (x-1) *(1+x) *(x^4 + x^3 + x^2 + x + 1) *(x^4 - x^3 + x^2 - x + 1) ). - _R. J. Mathar_, Mar 10 2011
%F A131579 Decimal expansion of 41028683/1111111110 . - _R. J. Mathar_, Jul 06 2025
%t A131579 PadRight[{}, 120, {0, 3, 6, 9, 2, 5, 8, 1, 4, 7}] (* _Vincenzo Librandi_, Aug 15 2017 *)
%o A131579 (Magma) &cat[[0,3,6,9,2,5,8,1,4,7]^^10]; // _Vincenzo Librandi_, Aug 15 2017
%Y A131579 Cf. A022336, A025648, A025655, A059626, A144468.
%K A131579 nonn,easy
%O A131579 0,2
%A A131579 _Paul Curtz_, Oct 02 2007