A227410 Palindromic prime numbers representing a date in "condensed American notation" MMDDYY.

10301, 10501, 10601, 11311, 11411, 12421, 12721, 12821, 30103, 30203, 30403, 30703, 30803, 31013, 31513, 32323, 32423, 70207, 70507, 70607, 71317, 71917, 72227, 72727, 73037, 90709, 91019

Offset: 1

Author

Shyam Sunder Gupta, Sep 22 2013

Keywords

• nonn
• base
• fini
• full
• less

Comments

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 27 terms. The largest term is a(27)=91019.

Examples

			a(1)=10301 is palindromic prime and represents a date in MMDDYY format as 010301.
		

Crossrefs

Cf. A213184, A227409, A227411.

Programs

Mathematica

palindromicQ[n_] := TrueQ[IntegerDigits[n] == Reverse[IntegerDigits[n]]]; 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] && palindromicQ[a], AppendTo[t, a]], {d, 1, b}], {m, 1,
   12}, {y, 1, 99}]; Union[t]