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A145507 a(n+1)=a(n)^2+2*a(n)-2 and a(1)=7 0
7, 61, 3841, 14760961, 217885999165441, 47474308632322991920487055361, 2253809980117057347661794063813616885861274573005652951041 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

General formula for a(n+1)=a(n)^2+2*a(n)-2 and a(1)=k+1 is a(n)=Floor[((k + Sqrt[k^2 + 4])/2)^(2^((n+1) - 1))

MATHEMATICA

aa = {}; k = 7; Do[AppendTo[aa, k]; k = k^2 + 2 k - 2, {n, 1, 10}]; aa

or

k =6; Table[Floor[((k + Sqrt[k^2 + 4])/2)^(2^(n - 1))], {n, 2, 7}] (*Artur Jasinski*)

CROSSREFS

A145502-A145511

Sequence in context: A049402 A001830 A048287 * A047685 A171078 A180776

Adjacent sequences:  A145504 A145505 A145506 * A145508 A145509 A145510

KEYWORD

nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Oct 11 2008

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Last modified February 17 04:52 EST 2012. Contains 205985 sequences.