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%I #23 Sep 08 2022 08:46:07
%S 2,5,9,89,8009,64152089,4115490587216009,
%T 16937262773463574696951813104089
%N a(0)=2, a(1)=5; thereafter a(n) = product of all preceding terms, minus 1.
%H Robert Munafo, <a href="http://mrob.com/pub/math/nu-sequences.html#table">Some integer sequences</a>
%H Robert Munafo, <a href="http://mrob.com/pub/seq/coprime.html">Mutually coprime sequences</a>
%F a(n) == 8 mod 9, for n > 2. - _Ivan N. Ianakiev_, Apr 06 2014
%F a(n) = (a(n-1)+1)*a(n-1)-1, for n > 2. - _Zak Seidov_, Apr 06 2014
%e (9 + 1)*9 - 1 = 89, (89 + 1)*89 - 1 = 8009, (8009 + 1)*8009 - 1 = 64152089. - _Zak Seidov_, Apr 06 2014
%o (Magma) I:=[2, 5, 9]; [n le 3 select I[n] else Self(n-1)*(Self(n-1)+1)-1: n in [1..10]]; // _Vincenzo Librandi_, May 22 2014
%Y Cf. A144779-A144784, A239900.
%K nonn
%O 0,1
%A _N. J. A. Sloane_, Apr 05 2014
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