perplexus.info :: Numbers : Introducing sphenic numbers

Introducing sphenic numbers (Posted on 2018-10-14)

A sphenic number S.N. is a product of three distinct prime numbers.

a. Clearly each S.N. has 8 divisors. Show that not only S.N.s claim this feature.
b. Find the smallest consecutive pair n,n+1 of sphenic numbers.
c. Same for the smallest triplet.
d. Prove that sphenic quadruplet n,n+1,n+2,n+3 is "mission impossible".

No Solution Yet Submitted by Ady TZIDON

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Subject	Author	Date
solution	Charlie	2018-10-14 17:35:31
computer solution	Steven Lord	2018-10-14 09:28:54
Parts a, d (spoiler)	Steve Herman	2018-10-14 09:27:24

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