A091633 -id:A091633 - cp's OEIS frontend

A287534 Composite numbers whose digits are restricted to 1, 3, 7, and 9.

9, 33, 39, 77, 91, 93, 99, 111, 113, 117, 119, 133, 171, 177, 319, 333, 339, 371, 377, 391, 393, 399, 711, 713, 717, 731, 737, 771, 777, 779, 791, 793, 799, 913, 917, 931, 933, 939, 973, 979, 993, 999

Offset: 1

Luke Zieroth, May 26 2017

Cf. A091633, A136333.

Select[Flatten@ Array[FromDigits /@ Tuples[{1, 3, 7, 9}, #] &, 3], CompositeQ] (* Michael De Vlieger, Jun 01 2017 *)

A323579 Primes formed by using the four terminal digits of multidigit primes and whose digits are distinct, i.e., consisting of only digits 1, 3, 7, 9.

Original entry on oeis.org

3, 7, 13, 17, 19, 31, 37, 71, 73, 79, 97, 137, 139, 173, 179, 193, 197, 317, 379, 397, 719, 739, 937, 971, 1973, 3719, 3917, 7193, 9137, 9173, 9371

Offset: 1

Bernard Schott, Jan 24 2019

There are only 31 terms in this sequence, which is a finite subsequence of A091633 and of A155045.

719 is also the third factorial prime belonging to A055490.

			1973 and 9371 are respectively the smallest and the largest primes formed with the four digits that can end multidigit primes.

Chris K. Caldwell and G. L. Honaker, Jr., 9371, Prime Curios!

Subsequence of A091633 and hence of A030096.

Cf. A029743 (with distinct digits), A124674 (with distinct prime digits), A155024 (with distinct nonprime digits but with 0), A155045 (with distinct odd digits), A323387 (with distinct square digits), A323391 (with distinct nonprime digits), A323578 (with distinct digits for which parity of digits alternates).

With[{w = Select[Range@ 10, GCD[#, 10] == 1 &]}, Select[FromDigits /@ Permutations[w, Length@ w], PrimeQ]] (* Michael De Vlieger, Feb 03 2019 *)
Select[FromDigits/@Flatten[Permutations/@Subsets[{1,3,7,9}],1],PrimeQ]//Union (* Harvey P. Dale, Apr 20 2025 *)

cp's OEIS Frontend

A287534 Composite numbers whose digits are restricted to 1, 3, 7, and 9.

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