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A092025
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Numbers k such that the concatenation of the first k positive integers plus prime(k) 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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For n > 1, a(n) is even.
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LINKS
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EXAMPLE
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66 is in the sequence because 1.2.3...65.66 + prime(66) is prime.
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MATHEMATICA
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n=1; Monitor[Parallelize[While[True, If[PrimeQ[Prime[n]+FromDigits[Join@@IntegerDigits/@Range[n]]], Print[n]]; n++]; n], n] (* J.W.L. (Jan) Eerland, Mar 03 2023 *)
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CROSSREFS
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KEYWORD
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nonn,base,more,changed
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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