|
%I #16 Sep 08 2022 08:46:13
%S 2,7,11,17,71,127,211,227,271,277,727,1117,1171,1217,1277,1721,1777,
%T 2111,2221,2711,2777,7121,7127,7177,7211,7717,7727,11117,11171,11177,
%U 11717,11777,12211,12227,12277,12721,17117,21121,21211,21221,21227,21277,21727
%N Primes that contain only the digits (1, 2, 7).
%C A020450, A020455 and A020459 are subsequences.
%H Alois P. Heinz, <a href="/A260889/b260889.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Prime[Range[2 10^5]], Complement[IntegerDigits[#], {1, 2, 7}] == {} &]
%t Table[Select[FromDigits/@Tuples[{1,2,7},n],PrimeQ],{n,5}]//Flatten (* _Harvey P. Dale_, Apr 12 2018 *)
%o (Magma) [p: p in PrimesUpTo(3*10^4) | Set(Intseq(p)) subset [1, 2, 7]];
%Y 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).
%Y Cf. A020450, A020455, A020459.
%K nonn,easy,base
%O 1,1
%A _Vincenzo Librandi_, Aug 04 2015
|
