A108634 Semiprimes with ordered digits.

4, 6, 9, 14, 15, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 55, 57, 58, 69, 77, 111, 115, 118, 119, 122, 123, 129, 133, 134, 145, 146, 155, 158, 159, 166, 169, 177, 178, 226, 235, 237, 247, 249, 259, 267, 278, 289, 299, 334, 335, 339, 346, 355, 358, 377, 445, 446

Offset: 1

Author

Zak Seidov, Jun 14 2005

Keywords

• nonn
• base

Programs

Mathematica

Select[Range[1000], Plus@@Last/@FactorInteger[ # ]==2&&OrderedQ[IntegerDigits[ # ]]&]