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A020742 Pisot sequence T(7,9). 4
7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

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

Tanya Khovanova, Recursive Sequences

Index entries for linear recurrences with constant coefficients, signature (2, -1).

FORMULA

a(n) = 2n+7. a(n) = 2a(n-1) - a(n-2).

MATHEMATICA

T[x_, y_, z_] := Block[{a}, a[0] = x; a[1] = y; a[n_] := a[n] = Floor[a[n - 1]^2/a[n - 2]]; Table[a[n], {n, 0, z}]]; T[7, 9, 66] (* Michael De Vlieger, Aug 08 2016 *)

PROG

(PARI) pisotT(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]));

  a

}

pisotT(50, 7, 9) \\ Colin Barker, Aug 08 2016

CROSSREFS

Subsequence of A005408, A020735. See A008776 for definitions of Pisot sequences.

Sequence in context: A004169 A066669 A059808 * A193071 A023389 A248963

Adjacent sequences:  A020739 A020740 A020741 * A020743 A020744 A020745

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified April 28 05:37 EDT 2017. Contains 285557 sequences.