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A048523
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Primes for which only one iteration of 'Prime plus its digit sum equals a prime' is possible.
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8
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13, 19, 37, 53, 71, 73, 97, 103, 127, 163, 181, 233, 271, 307, 383, 389, 431, 433, 499, 509, 563, 587, 631, 701, 743, 787, 811, 857, 859, 947, 1009, 1049, 1061, 1087, 1153, 1171, 1223, 1283, 1423, 1483, 1489, 1553, 1597, 1601, 1607, 1733, 1801, 1861, 1867
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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prime 1999 -> 1999 + (1+9+9+9) = prime 2027 -> next iteration yields composite 2038.
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MATHEMATICA
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ppd1Q[n_]:=PrimeQ[Rest[NestList[#+Total[IntegerDigits[#]]&, n, 2]]] == {True, False}; Select[Prime[Range[300]], ppd1Q] (* Harvey P. Dale, Nov 10 2011 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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