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A226105 Numbers n such that phi(n)+3 divides n+3 and floor(n/6) is not a prime. 0

%I

%S 1,195,5187

%N Numbers n such that phi(n)+3 divides n+3 and floor(n/6) is not a prime.

%C a(4) > 4*10^12. - _Giovanni Resta_, Jul 14 2013

%t Select[Range[10000000], !IntegerQ[#/6] && IntegerQ[(# + 3)/(EulerPhi[#] + 3)] &]

%o (PARI) for(n=1,10^8,if((n+3)%(eulerphi(n)+3)==0&&!isprime(n\6),print(n)))

%Y Cf. A226104.

%K nonn,hard,more,bref

%O 1,2

%A _José María Grau Ribas_, May 26 2013

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Last modified January 26 06:23 EST 2022. Contains 350572 sequences. (Running on oeis4.)