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Variant of Sylvester's sequence: a(n+1) = a(n)^2 - a(n) + 1, with a(1) = 11.
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%I #22 Aug 29 2020 13:11:32

%S 11,111,12211,149096311,22229709804712411,

%T 494159998001727075769152612720511,

%U 244194103625066907517263589918036880566782292998362610615987380611

%N Variant of Sylvester's sequence: a(n+1) = a(n)^2 - a(n) + 1, with a(1) = 11.

%C For the "exact" formula, compare the Aho-Sloane reference in A000058. - _N. J. A. Sloane_, Apr 07 2014

%H A. V. Aho and N. J. A. Sloane, <a href="https://www.fq.math.ca/Scanned/11-4/aho-a.pdf">Some doubly exponential sequences</a>, Fib. Quart., 11 (1973), 429-437.

%H Mohammad K. Azarian, <a href="http://www.jstor.org/stable/10.4169/college.math.j.42.4.329">Sylvester's Sequence and the Infinite Egyptian Fraction Decomposition of 1, Problem 958</a>, College Mathematics Journal, Vol. 42, No. 4, September 2011, p. 330.

%H Mohammad K. Azarian, <a href="http://www.jstor.org/stable/10.4169/college.math.j.43.4.337">Sylvester's Sequence and the Infinite Egyptian Fraction Decomposition of 1, Solution</a> College Mathematics Journal, Vol. 43, No. 4, September 2012, pp. 340-342.

%F a(n+1) = a(n)^2 - a(n) + 1, with a(1) = 11.

%F a(n) ~ c^(2^n) where c = 3.242214... (see A144808).

%t a = {}; r = 11; Do[AppendTo[a, r]; r = r^2 - r + 1, {n, 1, 10}]; a

%Y Cf. A000058, A082732, A144779, A144780, A144781, A144782, A144783, A144784, A144785, A144786, A144787, A144788, A144808.

%Y See A239900 for another version.

%K nonn

%O 1,1

%A _Artur Jasinski_, Sep 21 2008