Search: id:A033888 Results 1-1 of 1 results found. %I A033888 %S A033888 0,3,21,144,987,6765,46368,317811,2178309,14930352,102334155, %T A033888 701408733,4807526976,32951280099,225851433717,1548008755920, %U A033888 10610209857723,72723460248141,498454011879264,3416454622906707 %N A033888 Fibonacci(4n). %C A033888 (x,y)=(a(n),a(n+1)) are solutions of (x+y)^2/(1+xy)=9, the other solutions are in A033890.- Floor van Lamoen (fvlamoen(AT)hotmail.com), Dec 10 2001 %C A033888 Sequence A033888 provides half of the solutions to the equation 5*x^2 + 4 is a square. The other half are found in A033890. Lim. n-> Inf. a(n)/a(n-1) = phi^4 = (7+3*Sqrt(5))/2. - Gregory V. Richardson (omomom(AT)hotmail.com), Oct 13 2002 %H A033888 Index entries for sequences related to linear recurrences with constant coefficients %H A033888 Tanya Khovanova, Recursive Sequences %F A033888 a(n)=7a(n-1)-a(n-2). %F A033888 a(n) = [(7+3*Sqrt(5))^(n-1) - (7-3*Sqrt(5))^(n-1)] / ((2^(n-1))*Sqrt(5)) - Gregory V. Richardson (omomom(AT)hotmail.com), Oct 13 2002 %F A033888 a(n) = sum(k=0, n, F(3n-k)*binomial(n, k)) - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 07 2004 %F A033888 Lucas(2n) * Lucas(n) * Fibonacci(n). - R. Stephan, Sep 25 2004 %F A033888 G.f.: 3x/(1-7x+x^2). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 17 2008] %p A033888 (Mupad) numlib::fibonacci(n*4) $ n = 0..30; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 08 2008 %p A033888 sage: [lucas_number1(n,3,1)*lucas_number2(n,3,1) for n in xrange(0,21)] - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 29 2008 %t A033888 Table[Fibonacci[4*n],{n,0,14}] (Vladimir Orlovsky, Jul 21 2008) %o A033888 sage: [lucas_number1(n,3,1)*lucas_number2(n,3,1) for n in xrange(0,21)] - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 28 2008 %o A033888 (Other) sage: [fibonacci(4*n) for n in xrange(0, 20)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 15 2009] %Y A033888 Cf. A000045. %Y A033888 Fourth column of array A102310. %Y A033888 Sequence in context: A079753 A137969 A054419 this_sequence A141492 A088088 A037761 %Y A033888 Adjacent sequences: A033885 A033886 A033887 this_sequence A033889 A033890 A033891 %K A033888 nonn,easy %O A033888 0,2 %A A033888 N. J. A. Sloane (njas(AT)research.att.com). Search completed in 0.002 seconds