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A051416 Primes whose digits are composite. 5
89, 449, 499, 4649, 4889, 4969, 4999, 6449, 6469, 6689, 6869, 6899, 6949, 8669, 8689, 8699, 8849, 8969, 8999, 9649, 9689, 9949, 44449, 44699, 46489, 46499, 46649, 46889, 48449, 48649, 48869, 48889, 48989, 49499, 49669, 49999, 64489, 64499, 64849, 64969, 66449 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Chris Caldwell, The Prime Glossary, Composite number

G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 89

EXAMPLE

89 is the smallest composite-digit prime and also the only composite-digit prime whose digits are distinct. - Bernard Schott, Jan 31 2019

MATHEMATICA

Select[Prime@Range[6500], Intersection[IntegerDigits[ # ], {0, 1, 2, 3, 5, 7}] == {} & ] (* Ray Chandler, Mar 04 2007 *)

With[{c = {4, 6, 8, 9}}, Array[Select[Map[FromDigits@ Append[#, 9] &, Tuples[c, {#}]], PrimeQ] &, 4]] // Flatten (* Michael De Vlieger, Feb 02 2019 *)

CROSSREFS

Cf. A019546 (with prime digits), A030096 (with odd digits), A061246 (with square digits), A061371 (composite numbers with prime digits).

Subsequence of A061372 and of A152313.

Sequence in context: A083473 A142186 A142757 * A279366 A142904 A172523

Adjacent sequences:  A051413 A051414 A051415 * A051417 A051418 A051419

KEYWORD

nonn,easy,base,less

AUTHOR

G. L. Honaker, Jr., Jan 17 2000

EXTENSIONS

Extended by Ray Chandler, Mar 04 2007

STATUS

approved

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Last modified July 9 13:27 EDT 2020. Contains 335543 sequences. (Running on oeis4.)