A088608 - OEIS

%I #6 May 22 2021 17:37:01

%S 1,6,8,7,10,13,14,19,23,29,20,37,22,43,47,53,27,61,30,71,73,79,35,89,

%T 97,101,103,107,44,113,46,131,137,139,149,151,54,163,167,173,58,181,

%U 62,193,197,199,66,223,227,229,233,239,75,251,257,263,269,271,82,281,85,293

%N a(1) = 1, a(n) = prime(n) if n is composite else a(n) = composite(n).

%e a(9) = 23 = prime(9).

%t Join[{1},Module[{nn=100,cmps},cmps=Select[Range[2nn],CompositeQ];Table[ If[ PrimeQ[n],cmps[[n]],Prime[n]],{n,2,nn}]]] (* _Harvey P. Dale_, May 22 2021 *)

%Y Cf. A088607.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Oct 16 2003

%E More terms from _Ray Chandler_, Oct 18 2003