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%I #24 Sep 08 2022 08:46:05
%S 11,53,109,1789,3581,28669,229373,3670013,58720253,117440509,
%T 60129542141,264452523040700131966973,34662321099990647697175478269,
%U 2381976568446569244243622252022377480189,4878288012178573812210938372141829079433213
%N Primes in the chain of repeated application of x->2*x+3, starting at x=11.
%C Primes in A156127.
%H Vincenzo Librandi, <a href="/A225582/b225582.txt">Table of n, a(n) for n = 1..26</a>
%t Select[NestList[2 # + 3 &, 11, 30], PrimeQ] (* or *) Select[Table[7 2^n - 3, {n, 0, 150}], PrimeQ]
%o (Magma) x:=11; a:=[n eq 1 select x else 2*Self(n-1)+3: n in [1..200]]; [a[i]: i in [1..#a] | IsPrime(a[i])]; /* or */ [a: n in [0..150] | IsPrime(a) where a is 7*2^n-3];
%Y Primes of the form k*2^m-3: A050415 (k=1), A173769 (k=5), this sequence (k=7), A225583 (k=11), A225584 (k=13); A172156 (k=100), A163589 (k=715).
%Y Numbers of the form 7*2^m-3: A156127.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, May 14 2013
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