[seqfan] Erasing the integer to the right of a prime

[Eric Angelini]

Hello SeqFans,
S=1,2,2,3,4,2,5,6,3,7,8,4,2,9,5,10,6,3,11,12,7,13,14,8,4,2,15,9,5,16,10,6,3,17,18,11,19,20,12,7,21,13,22,14,8,4,2,23,24,15,9,5,25,...

1) Underline all integers that have a prime as left neighbour;
2) Now erase all underlined integers;

... the remining integers rebuild S.

P.-S.
S is build such that the underlined integers appear in this "natural" order:
2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,...
Best,
É.