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A164932
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Prime numbers in which the sum of the largest digit and the smallest digit is also a prime.
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1
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11, 23, 29, 41, 43, 47, 61, 67, 83, 89, 103, 107, 163, 211, 223, 229, 233, 239, 241, 269, 293, 307, 383, 421, 431, 433, 443, 449, 457, 461, 467, 479, 499, 503, 523, 547, 587, 607, 613, 631, 641, 647, 661, 677, 683, 701, 829, 853, 857, 863, 883, 929, 947
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OFFSET
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1,1
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COMMENTS
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If there is more than one digit with the same value (like in 211) only one is counted.
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LINKS
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EXAMPLE
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The sum of the largest digit and the smallest digit in the prime 947 is also a prime.
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MATHEMATICA
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sldsdQ[n_]:=Module[{idn=IntegerDigits[n]}, PrimeQ[Min[idn]+Max[idn]]]; Select[Prime[Range[200]], sldsdQ] (* Harvey P. Dale, Jul 17 2018 *)
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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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STATUS
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approved
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