A048587 Pisot sequence L(6,10).

6, 10, 17, 29, 50, 87, 152, 266, 466, 817, 1433, 2514, 4411, 7740, 13582, 23834, 41825, 73397, 128802, 226031, 396656, 696082, 1221538, 2143649, 3761841, 6601570, 11584947, 20330164, 35676950, 62608682, 109870577, 192809421, 338356946, 593775047, 1042002568

Offset

0,1

Links

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

Formula

a(n) = 3*a(n-1) - 3*a(n-2) + 2*a(n-3) - a(n-4) (holds at least up to n = 1000 but is not known to hold in general).

Mathematica

RecurrenceTable[{a[0] == 6, a[1] == 10, a[n] == Ceiling[a[n - 1]^2/a[n - 2]]}, a, {n, 0, 40}] (* Bruno Berselli, Feb 05 2016 *)

Prog

(Magma) Lxy:=[6, 10]; [n le 2 select Lxy[n] else Ceiling(Self(n-1)^2/Self(n-2)): n in [1..40]]; // Bruno Berselli, Feb 05 2016
(PARI) pisotL(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]));
  a
}
pisotL(50, 6, 10) \\ Colin Barker, Aug 07 2016

Crossrefs

Subsequence of A018908.

See A008776 for definitions of Pisot sequences.

Sequence in context: A315358 A049302 A020718 * A351661 A116001 A111617

Adjacent sequences: A048584 A048585 A048586 * A048588 A048589 A048590

Keyword

nonn

Author

David W. Wilson

Status

approved