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 A009970 #53 Mar 24 2025 22:34:39 %S A009970 1,26,676,17576,456976,11881376,308915776,8031810176,208827064576, %T A009970 5429503678976,141167095653376,3670344486987776,95428956661682176, %U A009970 2481152873203736576,64509974703297150976,1677259342285725925376,43608742899428874059776,1133827315385150725554176,29479510200013918864408576,766467265200361890474622976,19928148895209409152340197376 %N A009970 Powers of 26. %C A009970 Same as Pisot sequences E(1, 26), L(1, 26), P(1, 26), T(1, 26). Essentially same as Pisot sequences E(26, 676), L(26, 676), P(26, 676), T(26, 676). See A008776 for definitions of Pisot sequences. %C A009970 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 26-colored compositions of n such that no adjacent parts have the same color. - _Milan Janjic_, Nov 17 2011 %C A009970 Number of n-letter words over an alphabet with 26 letters. - _Wesley Ivan Hurt_, Apr 17 2016 %H A009970 T. D. Noe, <a href="/A009970/b009970.txt">Table of n, a(n) for n=0..100</a> %H A009970 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a> %H A009970 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (26). %F A009970 G.f.: 1/(1-26*x). - _Philippe Deléham_, Nov 23 2008 %F A009970 E.g.f.: exp(26*x). - _Zerinvary Lajos_, Apr 29 2009 %F A009970 From _Vincenzo Librandi_, Nov 21 2010: (Start) %F A009970 a(n) = 26*a(n-1) for n > 0, a(0) = 1. %F A009970 a(n) = 26^n. (End) %p A009970 A009970:=n->26^n: seq(A009970(n), n=0..25); # _Wesley Ivan Hurt_, Apr 17 2016 %t A009970 26^Range[0, 25] (* _Alonso del Arte_, Mar 25 2015 *) %t A009970 NestList[26#&,1,20] (* _Harvey P. Dale_, Jan 14 2017 *) %o A009970 (Sage) [lucas_number1(n,26,0) for n in range(1, 17)] # _Zerinvary Lajos_, Apr 29 2009 %o A009970 (Magma) [26^n: n in [0..100]]; // _Vincenzo Librandi_, Nov 21 2010 %o A009970 (Maxima) A009970(n):=26^n$ %o A009970 makelist(A009970(n),n,0,30); /* _Martin Ettl_, Nov 07 2012 */ %K A009970 nonn,easy %O A009970 0,2 %A A009970 _N. J. A. Sloane_