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A327918
The 16 pure prime dates of each non-leap year of the form concatenate(month,day) with month and day also prime numbers.
2
23, 211, 223, 37, 311, 313, 317, 331, 53, 523, 73, 719, 113, 1117, 1123, 1129
OFFSET
1,1
COMMENTS
For the numbers for leap years see A327919.
Only the months February (2), March (3), May (5), July (7) and November (11) qualify. The qualifying prime days are for month m=2: 3, 5, 7, 11, 13, 17, 19, 23; for month m = 11: 3, 5, 7, 11, 13, 17, 19, 23, 29 and for months m = 3, 5, and 7: 3, 5, 7, 11, 13, 17, 19, 23, 29, 31.
The months m = 2, 3, 5, 7, 11 contribute 3, 5, 2, 2, 4 days, respectively, adding to 16.
CROSSREFS
Cf. A165243 (first three terms), A165292 (first five terms), A165555 (first two terms), A167187 (first two terms), A327348 (m and d nonprime allowed), A327914 (with 0 before d = 1..9), A327919 (leap year), A327920 (pure prime dates of d.m form).
Sequence in context: A263521 A084428 A322287 * A327919 A165243 A142374
KEYWORD
nonn,easy,fini,full
AUTHOR
Wolfdieter Lang, Oct 08 2019
STATUS
approved