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A166851
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Numbers n such that reversal(n!+n) is prime.
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0
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OFFSET
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1,2
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COMMENTS
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It's obvious that 1 is the only number n such that n!+n is prime.
There is no further term up to 5000.
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LINKS
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EXAMPLE
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37!+37=13763753091226345046315979581580902400000037 and reversal(37!+37)=
73000000420908518597951364054362219035736731 is prime so 37 is in the sequence.
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MATHEMATICA
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reversal[n_]:=FromDigits[Reverse[IntegerDigits[n]]];
Do[If[PrimeQ[reversal[n!+n]], Print[n]], {n, 5000}]
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CROSSREFS
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KEYWORD
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base,hard,more,nonn
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AUTHOR
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STATUS
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approved
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