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A199346
Primes having only the (decimal) digits 3, 4 and 6.
3
3, 43, 433, 443, 463, 643, 3343, 3433, 3463, 3643, 4363, 4463, 4643, 4663, 6343, 33343, 36343, 36433, 36643, 43633, 44633, 46633, 46643, 46663, 63443, 63463, 64333, 64433, 64633, 64663, 66343, 66463, 66643, 333433, 334333, 334363, 334643, 336463, 336643, 343333, 343433, 344363, 346433, 363343, 363463, 364333, 364433, 364643
OFFSET
1,1
COMMENTS
All terms end in 3 and have a number of digits '4' that is not divisible by 3.
A020461 is a subsequence. - Vincenzo Librandi, Jul 29 2015
LINKS
MATHEMATICA
Select[Flatten[Table[FromDigits/@(Flatten[{#, 3}, 1]&/@Tuples[{3, 4, 6}, n]), {n, 0, 5}]], PrimeQ] (* Harvey P. Dale, Jan 01 2013 *)
Select[Prime[Range[10^5]], Complement[IntegerDigits[#], {3, 4, 6}]=={}&] (* Vincenzo Librandi, Jul 28 2015 *)
PROG
(PARI) a(n, list=0, L=[3, 4, 6], reqpal=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]), isprime(t=vector(d, i, L[v[i]])*u) || next; reqpal & !isprime(A004086(t)) & next; list & print1(t", "); n--|return(t)))}
(Magma) [p: p in PrimesUpTo(4*10^5) | Set(Intseq(p)) subset [3, 4, 6]]; // Vincenzo Librandi, Jul 29 2015
CROSSREFS
Cf. similar sequences listed in A199340.
Sequence in context: A321970 A199349 A197609 * A199340 A020461 A138974
KEYWORD
nonn,easy,base
AUTHOR
M. F. Hasler, Nov 05 2011
STATUS
approved