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 A009967 #57 Jul 10 2025 08:13:20 %S A009967 1,23,529,12167,279841,6436343,148035889,3404825447,78310985281, %T A009967 1801152661463,41426511213649,952809757913927,21914624432020321, %U A009967 504036361936467383,11592836324538749809,266635235464391245607,6132610415680998648961,141050039560662968926103,3244150909895248285300369,74615470927590710561908487,1716155831334586342923895201 %N A009967 Powers of 23. %C A009967 Same as Pisot sequences E(1, 23), L(1, 23), P(1, 23), T(1, 23). Essentially same as Pisot sequences E(23, 529), L(23, 529), P(23, 529), T(23, 529). See A008776 for definitions of Pisot sequences. %C A009967 The compositions of n in which each natural number is colored by one of p different colors are called p-colored compositions of n. For n>=1, a(n) equals the number of 23-colored compositions of n such that no adjacent parts have the same color. - _Milan Janjic_, Nov 17 2011 %C A009967 Numbers k such that sigma(23*k) = 23*k + sigma(k). - _Jahangeer Kholdi_, Nov 23 2013 %H A009967 T. D. Noe, <a href="/A009967/b009967.txt">Table of n, a(n) for n = 0..100</a> %H A009967 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>. %H A009967 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (23). %F A009967 G.f.: 1/(1-23*x). - _Philippe Deléham_, Nov 23 2008 %F A009967 a(n) = 23^n; a(n) = 23*a(n-1) n>0 a(0)=1. - _Vincenzo Librandi_, Nov 21 2010 %F A009967 From _Elmo R. Oliveira_, Jul 10 2025: (Start) %F A009967 E.g.f.: exp(23*x). %F A009967 a(n) = A009990(n)/A000079(n). (End) %t A009967 23^Range[0,20] (* _Harvey P. Dale_, Apr 04 2011 *) %o A009967 (SageMath) [lucas_number1(n,23,0) for n in range(1, 17)] # _Zerinvary Lajos_, Apr 29 2009 %o A009967 (Magma) [23^n: n in [0..100]]; // _Vincenzo Librandi_, Nov 21 2010 %o A009967 (Maxima) A009967(n):=23^n$ %o A009967 makelist(A009967(n),n,0,30); /* _Martin Ettl_, Nov 07 2012 */ %o A009967 (PARI) a(n)=23^n \\ _Charles R Greathouse IV_, Sep 24 2015 %Y A009967 Cf. A000079, A008776, A009990. %K A009967 nonn,easy %O A009967 0,2 %A A009967 _N. J. A. Sloane_