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Fibonacci entry points: a(n) = smallest m such that prime(A075702(n)) divides Fibonacci(m).
1

%I #2 Mar 30 2012 17:26:31

%S 432,127,1426,10488,63221,1328,11136,1291186

%N Fibonacci entry points: a(n) = smallest m such that prime(A075702(n)) divides Fibonacci(m).

%C In all cases, a(n) is one of divisors of (A075702(n)):

%C {2160,3048,27094,251712,505768,936240,2182656,2582372}/

%C {432,127,1426,10488,63221,1328,11136,1291186} = {5,24,19,24,8,705,196,2}.

%C This is used in Mathematica code for faster search.

%F a(n)=A001602(A075702(n)).

%e a(1)=432 because A075702(1)=2160=5*432, prime(2160)=19009, and F(432)/19009= 45104130506533126693784341438185160821786395872599778181861900641867287643757057395776.

%t s={2160,3048,27094,251712,505768,936240,2182656,2582372};

%t Do[sk=s[[k]]; dv=Divisors[sk]; i=2; While[Mod[Fibonacci[dvi=dv[[i]]],Prime[sk]]>0,i++ ]; Print[dvi], {k,8}]

%Y Cf. A001177, A001602, A075702.

%K nonn

%O 1,1

%A _Zak Seidov_, Nov 03 2009