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a(n) = n-th positive integer not relatively prime to n, with a(1)=1.
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%I #10 May 26 2023 17:03:56

%S 1,4,9,8,25,9,49,16,27,16,121,18,169,24,33,32,289,27,361,34,49,40,529,

%T 36,125,48,81,49,841,40,961,64,84,64,112,54,1369,72,102,66,1681,58,

%U 1849,80,96,88,2209,72,343,84,136,96,2809,81,200,98,153,112,3481,82

%N a(n) = n-th positive integer not relatively prime to n, with a(1)=1.

%C Final term of n-th row of A077661.

%H Franklin T. Adams-Watters, <a href="/A077662/b077662.txt">Table of n, a(n) for n = 1..1000</a>

%t Join[{1},Table[Select[Range[5000],!CoprimeQ[#,n]&][[n]],{n,2,60}]] (* _Harvey P. Dale_, May 26 2023 *)

%o (PARI) a(n) = local(i, k); if(n<=1,n,k=n-eulerphi(n);i=n\k;k*=i;i*=n; while(k<n,k+=(gcd(i++,n)!=1));i)

%Y Cf. A077661, A077663, A069213.

%Y A077149(n) - n - 1.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Nov 14 2002

%E More terms from _Sascha Kurz_, Jan 27 2003