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A117290 Numbers k for which the cototient k - phi(k) is a Fibonacci number. 0
2, 3, 4, 5, 7, 9, 11, 12, 13, 14, 16, 17, 19, 23, 25, 29, 31, 33, 37, 41, 43, 45, 47, 53, 57, 59, 61, 67, 71, 73, 79, 83, 85, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 159, 163, 167, 169, 173, 175, 179, 181, 191, 193, 197, 199, 211, 216, 223 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..61.

EXAMPLE

33 is in the sequence because 33 - phi(33) = 13, which is a Fibonacci number.

MATHEMATICA

With[{fibs=Fibonacci[Range[13]]}, Select[Range[fibs[[-1]]], MemberQ[fibs, #-EulerPhi[#]]&]]  (* Harvey P. Dale, Jan 28 2011 *)

CROSSREFS

Cf. A000045.

Sequence in context: A178434 A267439 A262691 * A286972 A210994 A319237

Adjacent sequences:  A117287 A117288 A117289 * A117291 A117292 A117293

KEYWORD

nonn

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), Apr 23 2006

STATUS

approved

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Last modified November 19 08:44 EST 2019. Contains 329318 sequences. (Running on oeis4.)