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A225582
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Primes in the chain of repeated application of x->2*x+3, starting at x=11.
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3
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11, 53, 109, 1789, 3581, 28669, 229373, 3670013, 58720253, 117440509, 60129542141, 264452523040700131966973, 34662321099990647697175478269, 2381976568446569244243622252022377480189, 4878288012178573812210938372141829079433213
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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Select[NestList[2 # + 3 &, 11, 30], PrimeQ] (* or *) Select[Table[7 2^n - 3, {n, 0, 150}], PrimeQ]
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PROG
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(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];
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CROSSREFS
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Numbers of the form 7*2^m-3: A156127.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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