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A109172 Recursive form of A109845 without a(2)=3. 0
2, 7, 41, 1723, 2967005, 8803121637031, 77494950556354550188857929 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..7.

FORMULA

a(1)=2, a(n)=a(n-1)^2+(-1)^n*a(n-1)+(-1)^n

MAPLE

a := proc(n) option remember; if n=1 then 2 else a(n-1)^2+(-1)^n*a(n-1)+(-1)^n fi end:

MATHEMATICA

nxt[{n_, a_}]:={n+1, a^2+(-1)^(n+1) a+(-1)^(n+1)}; Transpose[NestList[nxt, {1, 2}, 10]][[2]] (* Harvey P. Dale, Dec 15 2012 *)

CROSSREFS

Cf. A109845.

Sequence in context: A159315 A191601 A265772 * A131682 A317349 A158840

Adjacent sequences:  A109169 A109170 A109171 * A109173 A109174 A109175

KEYWORD

nonn

AUTHOR

Walter Kehowski, Aug 18 2005

STATUS

approved

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Last modified January 28 03:28 EST 2020. Contains 331314 sequences. (Running on oeis4.)