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A121215 a(1)=1. a(n) = n-th integer from among those positive integers which do not occur earlier in the sequence and which are not coprime to n. 0

%I

%S 1,4,9,10,30,14,56,22,33,24,143,27,182,35,48,44,289,40,361,50,70,62,

%T 529,57,155,72,105,76,841,64,1023,96,114,94,140,84,1369,110,132,100,

%U 1681,90,1849,124,144,136,2256,112,406,128,180,154,2809,126,270,158,204,176

%N a(1)=1. a(n) = n-th integer from among those positive integers which do not occur earlier in the sequence and which are not coprime to n.

%e 2,3,6,8,12,14,15,16,...is the sequence of positive integers which do not occur among the first 5 terms of the sequence and which are not coprime to 6. 14 is the 6th of these integers, so a(6) = 14.

%Y Cf. A105054.

%K nonn

%O 1,2

%A _Leroy Quet_, Aug 20 2006

%E Extended by _Ray Chandler_, Aug 22 2006

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Last modified February 2 05:15 EST 2023. Contains 359997 sequences. (Running on oeis4.)