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 A036123 #27 Sep 08 2022 08:44:52 %S A036123 1,3,9,27,19,26,16,17,20,29,25,13,8,24,10,30,28,22,4,12,5,15,14,11,2, %T A036123 6,18,23,7,21,1,3,9,27,19,26,16,17,20,29,25,13,8,24,10,30,28,22,4,12, %U A036123 5,15,14,11,2,6,18,23,7,21,1,3 %N A036123 a(n) = 3^n mod 31. %D A036123 I. M. Vinogradov, Elements of Number Theory, pp. 220 ff. %H A036123 G. C. Greubel, <a href="/A036123/b036123.txt">Table of n, a(n) for n = 0..10000</a> %H A036123 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,0,0,0,0,0,0,-1,1). %F A036123 a(n) = a(n+30). - _R. J. Mathar_, Jun 04 2016 %F A036123 a(n) = a(n-1) - a(n-15) + a(n-16). - _G. C. Greubel_, Oct 16 2018 %F A036123 a(n) = 31 - a(n+15) for all n in Z. - _Michael Somos_, Oct 17 2018 %p A036123 [ seq(primroot(ithprime(i))^j mod ithprime(i),j=0..100) ]; %t A036123 PowerMod[3, Range[0, 100], 31] (* _G. C. Greubel_, Oct 16 2018 *) %o A036123 (PARI) a(n)=lift(Mod(3,31)^n) \\ _Charles R Greathouse IV_, Mar 22 2016 %o A036123 (Magma) [Modexp(3, n, 31): n in [0..100]]; // _G. C. Greubel_, Oct 18 2018 %o A036123 (GAP) List([0..65],n->PowerMod(3,n,31)); # _Muniru A Asiru_, Oct 18 2018 %Y A036123 Cf. A000244 (3^n). %K A036123 nonn,easy %O A036123 0,2 %A A036123 _N. J. A. Sloane_