[seqfan] Re: Searching for "Sophie Germain 5-almost primes"

[Robert G. Wilson v]

Don,

	What about the least k-almost Sophie Germain primes?

Bob.

-----Original Message-----
From: SeqFan [mailto:seqfan-bounces at list.seqfan.eu] On Behalf Of Don Reble
Sent: Wednesday, January 30, 2013 3:00 AM
To: Sequence Fanatics Discussion list
Subject: [seqfan] Re: Searching for "Sophie Germain 5-almost primes"

> ... an integer N with exactly 5 prime factors (not necessarily
> distinct) such that 2N+1 also has exactly 5 prime factors:
>
> 688 = 2^4 * 43
> 2*688 + 1 = 1377 = 3^4 * 17

    Easy puzzle: what's this?

    2 4 52 40 688 4900 63112 178240 38272 5357056 1997824 247221760
    586504192 707436544

-- 
Don Reble  djr at nk.ca


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