A051416 - OEIS

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A051416

Primes whose digits are composite.

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