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A073676
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Rearrangement of odd numbers not divisible by 5 such that every right concatenation of terms is a prime.
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1
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3, 1, 7, 21, 23, 19, 33, 9, 39, 27, 59, 43, 51, 47, 117, 61, 287, 97, 129, 83, 49, 17, 171, 157, 107, 91, 29, 109, 191, 397, 221, 103, 63, 99, 123, 321, 149, 207, 393, 699, 133, 539, 93, 387, 309, 273, 79, 1121, 249, 457, 243, 213, 137, 643, 443, 693, 67, 1023, 381, 623, 939, 169, 663, 89, 153, 679, 227, 1027
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OFFSET
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1,1
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COMMENTS
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The number 11 finally appears as a(201).
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LINKS
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EXAMPLE
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3,31,3119,311951,31195117 are all prime.
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MATHEMATICA
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used={3}; num=3; Do[n=1; d=IntegerDigits[num]; While[MemberQ[used, n] || !PrimeQ[newNum=FromDigits[Join[d, IntegerDigits[n]]]], n=n+2]; AppendTo[used, n]; num=newNum, {50}]; used
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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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EXTENSIONS
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Corrected and extended by T. D. Noe, Jan 25 2011
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STATUS
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approved
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