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%I #10 Jul 25 2021 10:54:16
%S 1,9,2049,2057,4097,4105,6145,6153,524289,524297,526337,526345,528385,
%T 528393,530433,530441,16777217,16777225,16779265,16779273,16781313,
%U 16781321,16783361,16783369,17301505,17301513,17303553,17303561,17305601,17305609,17307649,17307657
%N Let a(1) = 1. Given a(1), ..., a(2^t), find the least k such that a(1) + 2^k, a(2) + 2^k, ..., a(2^t) + 2^k are all composite and a(1) + 2^k > a(2^t). Then a(2^t+i) = a(i) + 2^k for all 1 <= i <= 2^t.
%C This sequence can be represented by a single clause in a CNF IsPrime() function.
%o (PARI) step(v)=my(k=log(v[#v])\log(2));while(1, for(i=1,#v, k++; if(ispseudoprime(2^k+v[i]),next(2))); return(concat(v, vector(#v, i, 2^k+v[i])))) \\ _Charles R Greathouse IV_, Oct 25 2012
%K nonn
%O 1,2
%A _Russell Easterly_, Feb 14 2010
%E a(9)-a(32) from _Charles R Greathouse IV_, Oct 25 2012
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