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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 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 January 27 21:49 EST 2020. Contains 331299 sequences. (Running on oeis4.)