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 A216129 #13 Aug 09 2025 09:03:07 %S A216129 1,7,49,343,401,807,649,543,801,607,249,743,201,407,849,943,601,207, %T A216129 449,143,1,7,49,343,401,807,649,543,801,607,249,743,201,407,849,943, %U A216129 601,207,449,143,1,7,49,343,401,807,649,543,801,607,249,743,201,407,849,943,601,207,449,143,1 %N A216129 a(n) = 7^n mod 1000. %C A216129 Period = 20. %H A216129 Vincenzo Librandi, <a href="/A216129/b216129.txt">Table of n, a(n) for n = 0..1000</a> %H A216129 <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1). %t A216129 PowerMod[7, Range[0, 100], 1000] (* _Vincenzo Librandi_, Aug 16 2016 *) %o A216129 (PARI) for(i=0, 100, print(7^i%1000" ")) %o A216129 (Magma) [Modexp(7, n, 1000): n in [0..110]]; // _Vincenzo Librandi_, Aug 16 2016 %Y A216129 Cf. A001903, A014390. %K A216129 nonn,easy %O A216129 0,2 %A A216129 _V. Raman_, Sep 01 2012 %E A216129 a(0) = 1 prepended and offset changed by _Vincenzo Librandi_, Aug 16 2016