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A347612 Semiprimes formed from single-digits primes only, each used at most once. 1
25, 35, 57, 235, 237, 253, 327, 527, 537, 573, 723, 753, 2537, 2573, 2735, 5327, 5723, 7235 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

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

MATHEMATICA

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

CROSSREFS

Cf. A177061, A000040, A168349, A168385.

Sequence in context: A173251 A063149 A046423 * A331808 A153446 A039457

Adjacent sequences:  A347609 A347610 A347611 * A347613 A347614 A347615

KEYWORD

easy,base,fini,full,nonn

AUTHOR

Harvey P. Dale, Sep 08 2021

STATUS

approved

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Last modified July 7 12:08 EDT 2022. Contains 355148 sequences. (Running on oeis4.)