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Write down the squarefree positive integers, with a(1) = 1, and each m-th prime replaced with the m-th composite squarefree positive integer, and each m-th composite squarefree positive integer replaced with the m-th prime.
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%I #9 Feb 06 2019 16:22:35

%S 1,6,10,14,2,15,3,21,22,5,7,26,30,11,13,33,17,34,19,35,23,29,31,38,37,

%T 41,39,43,42,47,46,53,51,59,61,67,55,57,71,73,79,58,83,89,62,65,97,

%U 101,103,66,107,69,109,113,127,70,131,137,139,149,74,77,151,78

%N Write down the squarefree positive integers, with a(1) = 1, and each m-th prime replaced with the m-th composite squarefree positive integer, and each m-th composite squarefree positive integer replaced with the m-th prime.

%C This is a permutation of the squarefree positive integers.

%H Rémy Sigrist, <a href="/A163814/b163814.txt">Table of n, a(n) for n = 1..10000</a>

%H Rémy Sigrist, <a href="/A163814/a163814.gp.txt">PARI program for A163814</a>

%o (PARI) See Links section.

%Y Cf. A005117, A163813.

%K nonn

%O 1,2

%A _Leroy Quet_, Aug 04 2009

%E More terms from _Rémy Sigrist_, Feb 06 2019