[seqfan] Skolem/Langford pairs with primes

[Eric Angelini]

Hello SeqFans,
--> Between two integers k there are k primes.

The seq was always extended with the
smallest unused integer not leading to a
contradiction.
Every integer > 0 appears exactly twice
in the seq.

SL= 1,2,1,3,4,5,2,6,7,3,4,8,9,10,11,12,13,
5,14,15,16,17,6,18,19,20,21,22,23,7,
24,25,26,27,28,29,8,30,31,9,32,33,34,
35,36,37,10,38,39,40,41,42,43,11,12,
44,45,46,47,48,49,50,51,52,53,13,54,
59,14,60,61,15,62,63,64,65,66,67,16,
68,69,70,71,72,73,17,...

Example:
There is 1 prime (2) between the 1's;
2 primes (3,5) between the 2's
3 primes (5,2,7) between the 3's
4 primes (5,2,7,3) between the 4's
5 primes (2,7,3,11,13) between the 5's
6 primes (7,3,11,13,5,17) between the 6's
etc.

Done by hand on a mild day of Independence (Belgium).
Best,
É.