a(n-2) | (a(n)+a(n-1)): only primes
Antti Karttunen
antti.karttunen at gmail.com
Sun Jan 7 22:36:42 CET 2007
Peter Pein wrote:
>zak seidov schrieb:
>
>
>>Dear seqfans,
>>
>>Anyone with C++ may wish to add more terms?
>>
>>Thanks, Zak
>>
>>%S A000001
>>2,3,5,7,3,11,7,37,5,439,11,7013,379,27673,373,54973,977,548753,4229,7678313,10009,230339381,27763,5067438619,197297
>>%N A000001 a(1) =2 , a(2) = 3, a(n) = least prime such
>>that a(n-2) | (a(n)+a(n-1))
>>%A A000001 Zak Seidov (zakseidov at gmail.com), Jan 07
>>2007
>>
>>
>>
>Sorry,
>
>I do not understand, why a(3) = 5 > 3, because 2 | (3 + 3)
>??
>
>
I think it's a hidden unconscious assumption we are all sometimes guilty
of. In this case: "and different from the previous term".
-- Antti
>Peter
>
>
>
>
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