

A227407


Prime numbers representing a date in "condensed European notation" DDMMYY.


4



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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OFFSET

1,1


COMMENTS

For February, the number of days will be 28 only, as the year cannot be a leap year if DDMMYY is to be a prime number.
The sequence is finite, with 3111 terms. The largest term is a(3111)=311299.


LINKS



EXAMPLE

a(1)=10103 is prime and represents a date in DDMMYY format as 010103.


MATHEMATICA

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 m + y + 10000 d; If[PrimeQ[a], AppendTo[t, a]], {d, 1, b}], {m, 1, 12}, {y, 1, 99}]; Union[t]


CROSSREFS



KEYWORD

nonn,base,fini,full,less


AUTHOR



STATUS

approved



