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A227409
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Prime numbers representing a date in "condensed American notation" MMDDYY.
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4
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10103, 10111, 10133, 10139, 10141, 10151, 10159, 10163, 10169, 10177, 10181, 10193, 10211, 10223, 10243, 10247, 10253, 10259, 10267, 10271, 10273, 10289, 10301, 10303, 10313, 10321, 10331, 10333, 10337, 10343, 10357, 10369, 10391, 10399, 10427, 10429, 10433
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internal format)
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OFFSET
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1,1
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COMMENTS
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For February, the number of days will be 28 only, as the year cannot be a leap year if MMDDYY is to be a prime number.
The sequence is finite, with 3379 terms. The largest term is a(3379)=123191.
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LINKS
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EXAMPLE
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a(1)=10103 is prime and represents a date in MMDDYY format as 010103.
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MATHEMATICA
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t = {}; Do[If[m < 8, If[OddQ[m], b = 31, If[m == 2, b = 28, b = 30]], If[OddQ[m], b = 30, b = 31]]; Do[a = 100 d + y + 10000 m; If[PrimeQ[a], AppendTo[t, a]], {d, 1, b}], {m, 1, 12}, {y, 1, 99}]; Union[t]
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CROSSREFS
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KEYWORD
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nonn,base,fini,full,less
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AUTHOR
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STATUS
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approved
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