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A226105 Numbers n such that phi(n)+3 divides n+3 and floor(n/6) is not a prime. 0
1, 195, 5187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(4) > 4*10^12. - Giovanni Resta, Jul 14 2013

LINKS

Table of n, a(n) for n=1..3.

MATHEMATICA

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

PROG

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

CROSSREFS

Cf. A226104.

Sequence in context: A259694 A066232 A284960 * A164130 A084232 A145305

Adjacent sequences:  A226102 A226103 A226104 * A226106 A226107 A226108

KEYWORD

nonn,hard,more,bref

AUTHOR

José María Grau Ribas, May 26 2013

STATUS

approved

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Last modified December 2 14:09 EST 2021. Contains 349445 sequences. (Running on oeis4.)