A048626 Pisot sequence P(6,9).

6, 9, 13, 19, 28, 41, 60, 88, 129, 189, 277, 406, 595, 872, 1278, 1873, 2745, 4023, 5896, 8641, 12664, 18560, 27201, 39865, 58425, 85626, 125491, 183916, 269542, 395033, 578949, 848491, 1243524, 1822473, 2670964, 3914488, 5736961, 8407925, 12322413, 18059374

Offset

0,1

Links

Colin Barker, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (1,0,1).

Formula

a(n) = a(n-1) + a(n-3) (Checked up to n = 1000)

a(n) = A048625(n+1). - R. J. Mathar, Oct 15 2008

Mathematica

LinearRecurrence[{1, 0, 1}, {6, 9, 13}, 42] (* Robert G. Wilson v, Jul 12 2014 *)

Prog

(PARI) pisotP(nmax, a1, a2) = {
  a=vector(nmax); a[1]=a1; a[2]=a2;
  for(n=3, nmax, a[n] = ceil(a[n-1]^2/a[n-2]-1/2));
  a
}
pisotP(50, 6, 9) \\ Colin Barker, Aug 08 2016

Crossrefs

Subsequence of A048625, A000930. See A008776 for definitions of Pisot sequences.

Cf. A020721.

Sequence in context: A315968 A315969 A092949 * A002598 A315970 A315971

Adjacent sequences: A048623 A048624 A048625 * A048627 A048628 A048629

Keyword

nonn

Author

David W. Wilson

Status

approved