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A199342
Primes having only the (decimal) digits 2, 3 and 4.
4
2, 3, 23, 43, 223, 233, 433, 443, 2243, 2333, 2423, 3323, 3343, 3433, 4243, 4423, 22343, 22433, 23333, 24223, 24443, 32233, 32323, 32423, 32443, 33223, 33343, 42223, 42323, 42433, 42443, 43223, 222323, 223243, 223423, 224233, 224423, 224443, 232333, 232433, 233323, 233423, 234323, 234343, 242243, 243233, 243343, 243433, 244243, 244333
OFFSET
1,1
COMMENTS
A020458 and A020461 are subsequences. - Vincenzo Librandi, Jul 28 2015
LINKS
MATHEMATICA
Select[Prime[Range[10^5]], Complement[IntegerDigits[#], {3, 4, 2}]=={}&] (* Vincenzo Librandi, Jul 28 2015 *)
Table[Select[FromDigits/@Tuples[{2, 3, 4}, n], PrimeQ], {n, 6}]//Flatten (* Harvey P. Dale, Nov 06 2019 *)
PROG
(PARI) a(n, list=0, L=[2, 3, 4], 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(10^6) | Set(Intseq(p)) subset [3, 4, 2]]; // Vincenzo Librandi, Jul 28 2015
CROSSREFS
Cf. similar sequences listed in A199340.
Sequence in context: A309586 A090708 A359406 * A262838 A120366 A371310
KEYWORD
nonn,base,easy
AUTHOR
M. F. Hasler, Nov 05 2011
STATUS
approved