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%I #12 Oct 31 2013 17:56:06
%S 2,3,7,11,19,31,53,83,139,229,373,607,983,1583,2579,4177,6763,10939,
%T 17707,28649,46351,75017,121379,196387,317797,514219,832003,1346249,
%U 2178283,3524569,5702867,9227443,14930341,24157811,39088157,63245971
%N Largest prime immediately preceding a Fibonacci number.
%C Limit ratio of two consecutive elements of this sequence is phi=1.61803... the golden ratio.
%H Harvey P. Dale, <a href="/A180422/b180422.txt">Table of n, a(n) for n = 4..1000</a>
%e a(7)=53 that is the prime number preceding 55=fib(10).
%e fib(1)=1, fib(2)=1 and fib(3)=2 are not accounted.
%t NextPrime[#,-1]&/@Fibonacci[Range[4,40]] (* _Harvey P. Dale_, Oct 31 2013 *)
%o (PARI) a(n)=precprime(fibonacci(n)-1)
%Y Cf. A138184, A000045
%K nonn
%O 4,1
%A _Carmine Suriano_, Sep 03 2010
%E Program and cross-ref from _Charles R Greathouse IV_, Sep 08 2010
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