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A105850
a(n+1) = a(n)^2 - 2^(2^n+1) with a(1) = 8.
0
8, 56, 3104, 9634304, 92819813433344, 8615517765800787268541087744, 74227146372828989101844394431169040459931374583287906304
OFFSET
1,1
COMMENTS
Lehmer used this sequence in his proof of the Lucas-Lehmer test.
LINKS
D. H. Lehmer, On Lucas's Test for the Primality of Mersenne's Numbers, J. London Math. Soc., 10 (1935) 162-165.
FORMULA
a(n) = 2^(2^(n-1))*A003010(n).
MATHEMATICA
nxt[{n_, a_}]:={n+1, a^2-2^(2^n+1)}; Transpose[NestList[nxt, {1, 8}, 7]][[2]] (* Harvey P. Dale, Jul 24 2013 *)
CROSSREFS
Cf. A003010.
Sequence in context: A133671 A326239 A154411 * A009089 A296466 A202863
KEYWORD
nonn
AUTHOR
Douglas Stones (dssto1(AT)student.monash.edu.au), Apr 22 2005
STATUS
approved