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 A121218 a(n) = (n-th prime)th positive integer which is coprime to n. 0

%I

%S 2,5,7,13,13,37,19,37,34,71,34,109,44,99,88,105,62,181,70,177,127,173,

%T 86,265,121,217,154,249,112,421,131,261,226,295,216,451,161,343,271,

%U 431,183,631,195,423,368,415,215,667,264,571,370,517,245,751,353,613,425

%N a(n) = (n-th prime)th positive integer which is coprime to n.

%t f[s_List] := Block[{k = 0, l, n}, l = 1 + Length@s; n = Prime@l; While[n > 0, k++; While[ GCD[l, k] > 1, k++ ]; n-- ]; Return@ Append[s, k]]; Nest[f, {}, 75] (* _Ray Chandler_, Aug 22 2006 *)

%K nonn

%O 1,1

%A _Leroy Quet_, Aug 20 2006

%E Extended by _Ray Chandler_, Aug 22 2006

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Last modified November 30 21:57 EST 2022. Contains 358453 sequences. (Running on oeis4.)