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A086402
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Nontrivial numbers which are prime and yield another prime when their digits are sorted in descending order.
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2
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13, 17, 37, 79, 113, 131, 149, 157, 163, 167, 179, 181, 191, 197, 199, 241, 251, 281, 313, 337, 347, 359, 373, 389, 419, 461, 463, 491, 563, 571, 593, 613, 617, 683, 719, 787, 797, 839, 919, 1163, 1181, 1193, 1217, 1223, 1229, 1237, 1249, 1259, 1279, 1297
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OFFSET
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1,1
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COMMENTS
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Primes with digits already in descending order (like 311 and 3221) are trivial cases and are therefore excluded.
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LINKS
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EXAMPLE
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a(1)=13 because a descending sort of 13's digits yields 31 which is also prime. a(100)=2411 because a descending sort of 2411's digits yields 4211 which is also prime.
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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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Chuck Seggelin (barkeep(AT)plastereddragon.com), Jul 07 2003
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STATUS
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approved
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