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A260889
Primes that contain only the digits (1, 2, 7).
4
2, 7, 11, 17, 71, 127, 211, 227, 271, 277, 727, 1117, 1171, 1217, 1277, 1721, 1777, 2111, 2221, 2711, 2777, 7121, 7127, 7177, 7211, 7717, 7727, 11117, 11171, 11177, 11717, 11777, 12211, 12227, 12277, 12721, 17117, 21121, 21211, 21221, 21227, 21277, 21727
OFFSET
1,1
COMMENTS
A020450, A020455 and A020459 are subsequences.
LINKS
MATHEMATICA
Select[Prime[Range[2 10^5]], Complement[IntegerDigits[#], {1, 2, 7}] == {} &]
Table[Select[FromDigits/@Tuples[{1, 2, 7}, n], PrimeQ], {n, 5}]//Flatten (* Harvey P. Dale, Apr 12 2018 *)
PROG
(Magma) [p: p in PrimesUpTo(3*10^4) | Set(Intseq(p)) subset [1, 2, 7]];
CROSSREFS
Cf. Primes that contain only the digits (k,1,7): A199327 (k=0), this sequence (k=2), A260379 (k=3), A079651 (k=4), A260828 (k=5), A260891 (k=6), A260892 (k=8), A260893 (k=9).
Sequence in context: A045372 A273600 A103776 * A289994 A040154 A166862
KEYWORD
nonn,easy,base
AUTHOR
Vincenzo Librandi, Aug 04 2015
STATUS
approved