A260889 Primes that contain only the digits (1, 2, 7).

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

Alois P. Heinz, Table of n, a(n) for n = 1..10000

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).

Cf. A020450, A020455, A020459.

Sequence in context: A045372 A273600 A103776 * A289994 A040154 A166862

Adjacent sequences: A260886 A260887 A260888 * A260890 A260891 A260892

Keyword

nonn,easy,base

Author

Vincenzo Librandi, Aug 04 2015

Status

approved