A347612 Semiprimes formed from single-digits primes only, each used at most once.

25, 35, 57, 235, 237, 253, 327, 527, 537, 573, 723, 753, 2537, 2573, 2735, 5327, 5723, 7235

Offset: 1

Author

Harvey P. Dale, Sep 08 2021

Keywords

• easy
• base
• fini
• full
• nonn

Examples

			527 is a semiprime and its non-repeating digits are primes.
		

Crossrefs

Cf. A177061, A000040, A168349, A168385.

Programs

Mathematica

Select[FromDigits/@Flatten[Permutations/@Subsets[ {2,3,5,7}],1],PrimeOmega[ #] == 2&]//Union