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A048575 revision #32

A048575
Pisot sequences L(2,5), E(2,5).
2
2, 5, 13, 34, 89, 233, 610, 1597, 4181, 10946, 28657, 75025, 196418, 514229, 1346269, 3524578, 9227465, 24157817, 63245986, 165580141, 433494437, 1134903170, 2971215073, 7778742049, 20365011074, 53316291173, 139583862445, 365435296162, 956722026041
OFFSET
0,1
REFERENCES
Shalosh B. Ekhad, N. J. A. Sloane and Doron Zeilberger, Automated Proof (or Disproof) of Linear Recurrences Satisfied by Pisot Sequences, Preprint, 2016.
LINKS
Mohammad K. Azarian, Fibonacci Identities as Binomial Sums, International Journal of Contemporary Mathematical Sciences, Vol. 7, No. 38, 2012, pp. 1871-1876 (See Corollary 1 (ix)).
Tanya Khovanova, Recursive Sequences
FORMULA
a(n) = Fib(2n+3). a(n) = 3a(n-1) - a(n-2).
G.f.: (2-x)/(1-3x+x^2). [Philippe Deléham, Nov 16 2008]
a(n) = [(3/2)+(1/2)*sqrt(5)]^n+(2/5)*[(3/2)+(1/2)*sqrt(5)]^n*sqrt(5)-(2/5)*[(3/2)-(1/2)*sqrt(5)]^n *sqrt(5)+[(3/2)-(1/2)*sqrt(5)]^n, with n>=0. [Paolo P. Lava, Nov 20 2008]
MATHEMATICA
LinearRecurrence[{3, -1}, {2, 5}, 40] (* Vincenzo Librandi, Jul 12 2015 *)
PROG
(MAGMA) [Fibonacci(2*n+3): n in [0..40]]; // Vincenzo Librandi, Jul 12 2015
(PARI) pisotE(nmax, a1, a2) = {
a=vector(nmax); a[1]=a1; a[2]=a2;
for(n=3, nmax, a[n] = floor(a[n-1]^2/a[n-2]+1/2));
a
}
pisotE(50, 2, 5) \\ Colin Barker, Jul 27 2016
CROSSREFS
Subsequence of A001519. See A008776 for definitions of Pisot sequences.
Sequence in context: A141448 A011783 A001519 * A099496 A122367 A367658
KEYWORD
nonn,easy
STATUS
approved