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%I #18 Sep 08 2022 08:46:00
%S 7,11,17,71,101,107,701,1117,1171,1777,7001,7177,7717,10007,10111,
%T 10177,10711,10771,11071,11117,11171,11177,11701,11717,11777,17011,
%U 17077,17107,17117,17707,70001,70111,70117,70177,70717,71011,71171,71707,71711,71777,77017,77101,77171,77711,101107,101111,101117
%N Primes with digits '0', '1' and '7' only.
%H Harvey P. Dale, <a href="/A199327/b199327.txt">Table of n, a(n) for n = 1..10000</a>
%H James Maynard and Brady Haran, <a href="https://www.youtube.com/watch?v=eeoBCS7IEqs">Primes without a 7</a>, Numberphile video (2019).
%t f[i_,nn_]:=Select[Flatten[Table[FromDigits/@(Join[{i},#]&/@Tuples[ {0,1,7}, n]), {n,0,nn}]],PrimeQ]; Union[Join[f[1,6],f[7,6]]] (* _Harvey P. Dale_, Nov 19 2011 *)
%t Select[Prime[Range[2 10^4]], Complement[IntegerDigits[#], {0, 1, 7}]=={}&] (* _Vincenzo Librandi_, Jan 16 2020 *)
%o (PARI) a(n,list=0,L=[0,1,7])={for(d=1,1e9,my(t,u=vector(d,i,10^(d-i))~);forvec(v=vector(d,i,[1+!(L[1]||(i>1&&i<d)),#L]),ispseudoprime( t=vecextract(L,v)*u)||next;list&&print1(t",");n--||return(t)))} \\ Syntax updated for newer PARI versions by _M. F. Hasler_, Jul 26 2015
%o (Magma) [p: p in PrimesUpTo(80000) | Intseq(p) subset {0,1,7}]; // _Vincenzo Librandi_, Jan 16 2020
%Y Cf. A020449 - A020472, A036953, A260044, A260267 - A260271, A199325 - A199329, A061247, A199340 - A199349.
%K nonn,base
%O 1,1
%A _M. F. Hasler_, Nov 05 2011
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