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A059799
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Primes which when added to their reversals are squares.
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5
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2, 29, 47, 83, 263, 461, 20147, 23117, 24107, 63113, 80141, 81131, 300893, 301793, 303593, 308093, 310883, 313583, 324473, 333563, 336263, 342653, 344453, 348053, 350843, 354443, 355343, 356243, 362633, 363533, 364433, 365333, 377123, 378023
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OFFSET
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1,1
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COMMENTS
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Idea from Carlos Rivera's The Prime Puzzles and Problems Connection, Conjecture 23.
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LINKS
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FORMULA
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Add prime to its reverse. If a square, add to sequence.
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EXAMPLE
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a(4)=263 because 263+362=625 and 625 is a square whose root is 25.
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MATHEMATICA
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Select[Prime[Range[33000]], IntegerQ[Sqrt[FromDigits[Reverse[ IntegerDigits[#]]]+ #]]&] (* Harvey P. Dale, Aug 18 2012 *)
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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