

A181564


Semiprime convenient numbers.


0



4, 6, 9, 10, 15, 21, 22, 25, 33, 57, 58, 85, 93, 133, 177, 253
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OFFSET

1,1


COMMENTS

This is to semiprimes A001358 as A140768 is to primes A000040. Because Euler's "numerus idoneus" (idoneal, or suitable, or convenient numbers) are finite, this subset is finite. Conjecture: this list is complete (see Weinberger's result and comment by Jud McCranie in A140768).


LINKS



FORMULA



EXAMPLE

a(16) = A000926(50) = 253 = 11 * 23.


CROSSREFS



KEYWORD

nonn,fini


AUTHOR



STATUS

approved



