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

1,1

Links

Table of n, a(n) for n=1..42.

Mathematica

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

Crossrefs

Cf. A091633, A136333.

Sequence in context: A208136 A130444 A177697 * A145849 A111045 A020226

Adjacent sequences: A287531 A287532 A287533 * A287535 A287536 A287537

Keyword

nonn,base

Author

Luke Zieroth, May 26 2017

Status

approved