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A084201
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Primes p such that the sum of the digits is prime and the sum of the digits of 2p is also prime.
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2
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7, 29, 47, 61, 83, 137, 139, 151, 173, 191, 193, 227, 229, 263, 281, 283, 317, 337, 353, 373, 409, 461, 463, 557, 577, 599, 601, 641, 643, 733, 757, 797, 821, 823, 887, 911, 977, 1019, 1039, 1051, 1091, 1093, 1109, 1129, 1163, 1181, 1217, 1237, 1291
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OFFSET
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1,1
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COMMENTS
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Note that 137 and 139 are twin primes.
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LINKS
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EXAMPLE
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2+9=11=prime for 29 and 5+8=13=prime for 58=2*29;
1+3+7=11=prime for 137 and 2+7+4=13=prime for 274=2*137;
1+3+9=13=prime for 139 and 2+7+8=17=prime for 278=2*139.
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MAPLE
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filter:= proc(n)
isprime(n) and isprime(convert(convert(n, base, 10), `+`)) and isprime(convert(convert(2*n, base, 10), `+`))
end proc:
select(filter, [seq(i, i=3..5000, 2)]); # Robert Israel, Sep 04 2019
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MATHEMATICA
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Select[Prime[Range[300]], And@@PrimeQ[Total/@{IntegerDigits[#], IntegerDigits[2 #]}]&] (* Harvey P. Dale, Jun 26 2011 *)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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