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A206098 Fibonacci numbers F such that F and either F-3 or F+3 (or both) are the products of three distinct primes. 0
9227465, 7778742049, 17167680177565, 1500520536206896083277, 3311648143516982017180081, 50095301248058391139327916261, 898923707008479989274290850145, 23770696554372451866815101694984845480039225387896643963981 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

9227465 = 5*13*141961; 9227465-3 = 2*23*200597.

MATHEMATICA

Select[Fibonacci[Range[300]], Last/@FactorInteger[#]=={1, 1, 1} && (Last/@FactorInteger[#+3]=={1, 1, 1} || Last/@FactorInteger[#-3]=={1, 1, 1})&]

Select[Fibonacci[Range[300]], PrimeNu[#]==PrimeOmega[#]==3&& (PrimeNu[ #-3]==PrimeOmega[#-3]==3||PrimeNu[#+3]==PrimeOmega[#+3]==3)&] (* Harvey P. Dale, May 18 2019 *)

CROSSREFS

Cf. A000045

Sequence in context: A251399 A206599 A245746 * A105175 A212469 A251280

Adjacent sequences:  A206095 A206096 A206097 * A206099 A206100 A206101

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Feb 03 2012

EXTENSIONS

Definition clarified and example corrected by Harvey P. Dale, May 18 2019

STATUS

approved

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Last modified January 27 12:01 EST 2020. Contains 331295 sequences. (Running on oeis4.)