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%I #34 Apr 03 2023 10:36:09
%S 89,449,499,4649,4889,4969,4999,6449,6469,6689,6869,6899,6949,8669,
%T 8689,8699,8849,8969,8999,9649,9689,9949,44449,44699,46489,46499,
%U 46649,46889,48449,48649,48869,48889,48989,49499,49669,49999,64489,64499,64849,64969,66449
%N Primes whose digits are composite.
%C Primes formed by using only digits 4, 6, 8, 9. Of course, all the terms of this sequence end with 9. - _Bernard Schott_, Jan 31 2019
%H Alois P. Heinz, <a href="/A051416/b051416.txt">Table of n, a(n) for n = 1..10000</a>
%H Chris Caldwell, The Prime Glossary, <a href="https://t5k.org/glossary/xpage/Composite.html">Composite number</a>
%H G. L. Honaker, Jr. and Chris Caldwell, <a href="https://t5k.org/curios/cpage/646.html">Prime Curios! 89</a>
%e 89 is the smallest composite-digit prime and also the only composite-digit prime whose digits are distinct. - _Bernard Schott_, Jan 31 2019
%t Select[Prime@Range[6500], Intersection[IntegerDigits[ # ], {0, 1, 2, 3, 5, 7}] == {} & ] (* _Ray Chandler_, Mar 04 2007 *)
%t With[{c = {4, 6, 8, 9}}, Array[Select[Map[FromDigits@ Append[#, 9] &, Tuples[c, {#}]], PrimeQ] &, 4]] // Flatten (* _Michael De Vlieger_, Feb 02 2019 *)
%Y Cf. A019546 (with prime digits), A030096 (with odd digits), A061246 (with square digits), A061371 (composite numbers with prime digits).
%Y Subsequence of A061372 and of A152313.
%K nonn,easy,base,less
%O 1,1
%A _G. L. Honaker, Jr._, Jan 17 2000
%E Extended by _Ray Chandler_, Mar 04 2007
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