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A199342 Primes having only {2, 3, 4} as digits.

%I A199342 #21 Jul 14 2025 17:30:14
%S A199342 2,3,23,43,223,233,433,443,2243,2333,2423,3323,3343,3433,4243,4423,
%T A199342 22343,22433,23333,24223,24443,32233,32323,32423,32443,33223,33343,
%U A199342 42223,42323,42433,42443,43223,222323,223243,223423,224233,224423,224443,232333,232433,233323,233423,234323,234343,242243,243233,243343,243433,244243,244333
%N A199342 Primes having only {2, 3, 4} as digits.
%C A199342 A020458 and A020461 are subsequences. - _Vincenzo Librandi_, Jul 28 2015
%H A199342 Jason Bard, <a href="/A199342/b199342.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Harvey P. Dale)
%t A199342 Select[Prime[Range[10^5]], Complement[IntegerDigits[#], {3, 4, 2}]=={}&] (* _Vincenzo Librandi_, Jul 28 2015 *)
%t A199342 Table[Select[FromDigits/@Tuples[{2,3,4},n],PrimeQ],{n,6}]//Flatten (* _Harvey P. Dale_, Nov 06 2019 *)
%o A199342 (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)))}
%o A199342 (Magma) [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [3, 4, 2]]; // _Vincenzo Librandi_, Jul 28 2015
%Y A199342 Cf. A020449 - A020472, A199325 - A199329, A385768 - A385800.
%Y A199342 Cf. similar sequences listed in A199340.
%K A199342 nonn,base,easy
%O A199342 1,1
%A A199342 _M. F. Hasler_, Nov 05 2011