A094411 Composite numbers k that divide both Fibonacci(k+1) and Fibonacci(k) + 1.

5777, 10877, 75077, 80189, 100127, 113573, 161027, 162133, 231703, 430127, 618449, 635627, 667589, 851927, 1033997, 1106327, 1256293, 1388903, 1697183, 2263127, 2435423, 2512889, 2662277, 3175883, 3399527, 3452147, 3774377

Offset: 1

Author

Eric Rowland, May 01 2004

Keywords

• nonn
• changed

Comments

Also composites k that divide both Fibonacci(k+1) and Lucas(k) - 1. - Gary Detlefs, Feb 28 2013

Links

• Giovanni Resta, Table of n, a(n) for n = 1..548 (terms < 4*10^9)

Crossrefs

Cf. A000032, A000045, A002808, A069107, A094395, A094401, A094412.

Programs

Mathematica

Select[Range[2, 50000], ! PrimeQ[ # ] && Mod[Fibonacci[ # + 1], # ] == 0 && Mod[Fibonacci[ # ] + 1, # ] == 0 &]

Extensions

More terms from Gareth McCaughan, Jun 11 2004

More terms from Ryan Propper, Aug 04 2005

Offset corrected by Giovanni Resta, Jul 20 2013