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A199325
Primes with digits '0', '1' and '5' only.
25
5, 11, 101, 151, 1051, 1151, 1511, 5011, 5051, 5101, 5501, 10111, 10151, 10501, 11551, 15101, 15511, 15551, 50051, 50101, 50111, 50551, 51001, 51151, 51511, 51551, 55001, 55051, 55501, 55511, 100151, 100501, 100511, 101051, 101111, 101501, 110051, 110501, 115001, 115151, 150001, 150011, 150151, 150551
OFFSET
1,1
MAPLE
N:= 10000: # to get the first N terms
count:= 0:
allowed:= {0, 1, 5}:
nallowed:= nops(allowed):
subst:= seq(i=allowed[i+1], i=0..nallowed-1):
for d from 0 while count < N do
for x1 from 1 to nallowed-1 while count < N do
for t from 0 to nallowed^d-1 while count < N do
L:= subs(subst, convert(x1*nallowed^d+t, base, nallowed));
X:= add(L[i]*10^(i-1), i=1..d+1);
if isprime(X) then
count:= count+1;
A[count]:= X;
fi
od od od:
seq(A[n], n=1..N); # Robert Israel, Apr 20 2014
MATHEMATICA
Select[FromDigits/@Tuples[{0, 1, 5}, 6], PrimeQ] (* Harvey P. Dale, Jul 23 2021 *)
PROG
(PARI) L=[0, 1, 5]; for(d=1, 6, 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)&print1(t", "))) /* see A199327 for a function a(n) */
(Magma) [p: p in PrimesUpTo(160000) | Set(Intseq(p)) subset [0, 1, 5]]; // Vincenzo Librandi, Apr 22 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Nov 05 2011
STATUS
approved