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A207667 Numbers n such that phi(n) divides n+2. 0
1, 2, 4, 6, 10, 30, 70, 510, 2590, 131070, 3359230, 167247870, 8589934590 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(14) > 10^11. - Donovan Johnson, Mar 01 2012

a(14) > 10^13. - Giovanni Resta, May 05 2017

LINKS

Table of n, a(n) for n=1..13.

MATHEMATICA

Select[Range[50000000], Divisible[#+2, EulerPhi[#]]&]

CROSSREFS

Cf.  A000010 (Euler's totient function).

Cf.  A207574 (Numbers n such that phi(n)+2 divides n+2).

Cf.  A202855 (Numbers n such that phi(n)-1 divides n).

Cf.  A203966 (Numbers n such that phi(n) divides n+1).

Sequence in context: A095007 A005194 A171447 * A085809 A073308 A058960

Adjacent sequences:  A207664 A207665 A207666 * A207668 A207669 A207670

KEYWORD

nonn

AUTHOR

José María Grau Ribas, Feb 19 2012

EXTENSIONS

a(12)-a(13) from Donovan Johnson, Mar 01 2012

STATUS

approved

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Last modified January 25 08:51 EST 2022. Contains 350565 sequences. (Running on oeis4.)