[seqfan] Fun with prime runs

Eric Angelini Eric.Angelini at kntv.be
Fri Nov 19 16:36:27 CET 2010

Hello again SeqFans,
more from our "Silly Sequences' Storage".

Here is P:

P is a permutation of the Naturals (by definition) and
P self-describes its own prime runs' sizes of 
concatenated terms:


-concatenating the first 2 terms produces a prime --> 2+3 = '23'
-concatenating the next  3 terms produces a prime --> 1+4+23 = '1423'
-concatenating the next  1 term  produces a prime --> '5'
-concatenating the next  4 terms produces a prime --> 6+7+8+19 = '67819'
-concatenating the next 23 terms produces a prime --> but which one?

... I'm not sure that the term X (after 32), is computable...

As always, "in building this sequence, always use the smallest available
integer not leading to a contradiction"...

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