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%I #18 Sep 08 2022 08:46:13
%S 7,589,11064985,7835767761026353,7859104819806710982081319640824417,
%T 15811975313589523224392147529414564125936123169432771986649715567359169
%N Hall's sequence g_n.
%H James S. Hall, <a href="http://jlms.oxfordjournals.org/content/s1-28/3/285.extract">A remark on the primeness of Mersenne numbers</a>, J. London Math. Soc. 28, (1953), 285-287.
%F a(n) = g(n) where g(3) = 7 and g(n+1) = 2*(g(n)-1)*(1+2^n*(g(n)-1)) + 1.
%o (PARI) N=11; g=vector(N); g[3] = 7;
%o for (n=3, N-1, g[n+1] = 2*(g[n]-1)*(1+2^n*(g[n]-1))+1 );
%o vector(N-3, j, g[j+2])
%o (Magma) [n le 1 select 7 else 2*(Self(n-1)-1)*(1+2^(n+1)*(Self(n-1)-1)) + 1: n in [1..6]]; // _Vincenzo Librandi_, Aug 24 2015
%Y Cf. A002812, A003010.
%K nonn
%O 3,1
%A _Joerg Arndt_, Aug 24 2015
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