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 A064720 #12 Jun 03 2025 01:09:56
%S A064720 2,4,6,8,10,12,14,16,18,20,23,25,27,29,31,33,35,37,39,41,44,46,48,50,
%T A064720 52,54,56,58,60,62,65,67,69,71,73,75,77,79,81,83,86,88,90,92,94,96,98,
%U A064720 100,102,104,107,109,111,113,115,117,119,121,123,125,128,130,132,134
%N A064720 A Beatty sequence for 3^i + 3^-i + 1.
%C A064720 3^i + 3^-i + 1 ~= 1.90966484565321951005513028719008497... ~= 21/11.
%C A064720 Different from A059548, although the sequences agree for about 1400 terms. - _Joshua Zucker_, Apr 25 2007
%H A064720 Harry J. Smith, <a href="/A064720/b064720.txt">Table of n, a(n) for n = 1..2000</a>
%t A064720 a = Chop[ N[ 3^I + 3^-I +1, 36], 10^-40]; Table[ Floor[n*a/(a-1)], {n, 1, 75} ]
%o A064720 (PARI) { default(realprecision, 100); b=real(3^I + 3^-I) + 1; b=b/(b - 1); for (n = 1, 2000, write("b064720.txt", n, " ", floor(n*b)) ) } \\ _Harry J. Smith_, Sep 23 2009
%Y A064720 Cf. A064719.
%K A064720 easy,nonn
%O A064720 1,1
%A A064720 _Robert G. Wilson v_, Oct 13 2001