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Odd composites k that divide Fibonacci(k) + 1 but not Fibonacci(k+1).
2

%I #22 Jul 22 2024 00:03:10

%S 17261,120581,163059,300847,1842581,3489641,3792541,5573499,21159271,

%T 36561959,40779991,63055651,67306519,69503037,72125899,129487163,

%U 136021717,174008141,175094767,247600477,418623283,529281911,814454381,902315699

%N Odd composites k that divide Fibonacci(k) + 1 but not Fibonacci(k+1).

%H David Radcliffe, <a href="/A094413/b094413.txt">Table of n, a(n) for n = 1..33</a> (first 24 terms from G. Resta)

%o (PARI) isok(n) = (n % 2) && ! ((fibonacci(n) + 1) % n) && (fibonacci(n+1) % n); \\ _Michel Marcus_, Aug 27 2013

%Y Cf. A094395, A094411, A094412.

%K nonn

%O 1,1

%A _Eric Rowland_, May 07 2004

%E 4 more terms from _Ryan Propper_, Aug 03 2005

%E a(9)-a(24) from _Giovanni Resta_, Jul 20 2013