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A263482
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Numbers k such that k! + 2^k + 11 or k! + 2^k - 11 is prime.
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1
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0, 2, 3, 4, 5, 6, 7, 9, 15, 34, 41, 79, 99, 379, 2183
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OFFSET
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1,2
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COMMENTS
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Is there some k such that k! + 2^k + 11 and k! + 2^k - 11 are prime?
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LINKS
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EXAMPLE
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For k = 0, k! + 2^k + 11 = 0! + 2^0 + 11 = 13, which is prime.
For k = 3, k! + 2^k - 11 = 3! + 2^3 - 11 = 3, which is prime.
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MATHEMATICA
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Select[Range[0, 400], Or[PrimeQ[#! + 2^# + 11], PrimeQ[#! + 2^# - 11]] &] (* Michael De Vlieger, Nov 17 2015 *)
Select[Range[0, 500], AnyTrue[#!+2^#+{11, -11}, PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 05 2019 *)
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PROG
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(PARI) for(n=0, 1e3, if(isprime(n!+2^n-11) || isprime(n!+2^n+11), print1(n", ")))
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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