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A084201
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Primes n such that the sum of the digits is prime and the sum of the digits of 2n is also prime.
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0
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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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| Note that 137 and 139 are twin primes.
A049084(A007953(a(n)))*A049084(A007953(2*a(n))) > 0. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 26 2003
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EXAMPLE
| 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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MATHEMATICA
| Select[Prime[Range[300]], And@@PrimeQ[Total/@{IntegerDigits[#], IntegerDigits[2 #]}]&] (* From Harvey P. Dale, June 26 2011 *)
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CROSSREFS
| Sequence in context: A103603 A045465 A165492 * A031380 A005698 A080185
Adjacent sequences: A084198 A084199 A084200 * A084202 A084203 A084204
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KEYWORD
| base,nonn
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AUTHOR
| CAPELLE Patrick (patrick.capelle(AT)clearwire.be), Jun 20 2003
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EXTENSIONS
| More terms from Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 26 2003
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