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A061247 Primes having only {0, 1, 8} as digits.

%I A061247 #34 Jul 20 2025 18:07:05
%S A061247 11,101,181,811,881,1181,1801,1811,8011,8081,8101,8111,10111,10181,
%T A061247 11801,18181,80111,81001,81101,81181,88001,88801,88811,100801,100811,
%U A061247 101081,101111,108011,108881,110881,118081,118801,180001,180181,180811
%N A061247 Primes having only {0, 1, 8} as digits.
%C A061247 The intersection with A007500 is listed in A199328. - _M. F. Hasler_, Nov 05 2011
%H A061247 Robert Israel, <a href="/A061247/b061247.txt">Table of n, a(n) for n = 1..17482</a>
%e A061247 a(6) = 1801, 1801 is a prime and consists of only 1, 8 and 0.
%p A061247 N:= 1000: # to get the first N entries
%p A061247 count:= 0:
%p A061247 allowed:= {0,1,8}:
%p A061247 nallowed:= nops(allowed):
%p A061247 subst:= seq(i=allowed[i+1],i=0..nallowed-1);
%p A061247 for d from 1 while count < N do
%p A061247   for x1 from 1 to nallowed-1 while count < N do
%p A061247     for t from 0 to nallowed^d-1  while count < N do
%p A061247       L:= subs(subst,convert(x1*nallowed^d+t,base,nallowed));
%p A061247       X:= add(L[i]*10^(i-1),i=1..d+1);
%p A061247       if isprime(X) then
%p A061247           count:= count+1;
%p A061247           A[count]:= X;
%p A061247       fi
%p A061247 od od od:
%p A061247 seq(A[n],n=1..N); # _Robert Israel_, Apr 20 2014
%t A061247 Select[Prime[Range[50000]],Length[Union[{0,1,8},IntegerDigits[ # ]]] == 3&] (* _Stefan Steinerberger_, Jun 10 2007 *)
%t A061247 Select[FromDigits/@Tuples[{0,1,8},6],PrimeQ] (* _Harvey P. Dale_, Jan 12 2016 *)
%o A061247 (PARI) a(n=50, L=[0, 1, 8], show=0)={my(t); for(d=1, 1e9, u=vector(d, i, 10^(d-i))~; forvec(v=vector(d, i, [1+(i==1 && !L[1]), #L]), ispseudoprime(t=vector(d, i, L[v[i]])*u) || next; show && print1(t", "); n-- || return(t)))} \\ _M. F. Hasler_, Nov 05 2011
%o A061247 (Magma) [NthPrime(n): n in [1..2*10^4] | forall{d: d in Intseq(NthPrime(n)) | d in [0, 1, 8]}]; // _Vincenzo Librandi_, May 15 2019
%Y A061247 Cf. A061246, A020449-A020472, A199325-A199329.
%K A061247 nonn,base
%O A061247 1,1
%A A061247 _Amarnath Murthy_, Apr 23 2001
%E A061247 Corrected and extended by _Stefan Steinerberger_, Jun 10 2007