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A113188 Primes that are the difference of two Fibonacci numbers; primes in A007298. +0
12
2, 3, 5, 7, 11, 13, 19, 29, 31, 47, 53, 89, 131, 139, 199, 233, 521, 607, 953, 1453, 1597, 2207, 2351, 2579, 3571, 6763, 9349, 10891, 28513, 28649, 28657, 42187, 44771, 46279, 75017, 189653, 317777, 514229, 1981891, 2177699, 3010349, 3206767 (list; graph; listen)
OFFSET

1,1

COMMENT

The difference F(i)-F(j) equals the sum F(j-1)+...+F(i-2) [Corrected by Patrick Capelle, Mar 01 2008]. In general, we need gcd(i,j)=1 for F(i)-F(j) to be prime. The exceptions are handled by the following rule: if i and j are both even or both odd, then F(i)-F(j) is prime if either (1) i-j=4 and L(i-2) is a Lucas prime or (2) i-j=2 and F(i-1) is a Fibonacci prime.

EXAMPLE

The prime 139 is here because it is F(12)-F(5).

MATHEMATICA

lst={}; Do[p=Fibonacci[n]-Fibonacci[i]; If[PrimeQ[p], AppendTo[lst, p]], {n, 2, 40}, {i, n-1}]; Union[lst]

CROSSREFS

Cf. A000045 (Fibonacci numbers), A001605 (Fibonacci(n) is prime), A001606 (Lucas(n) is prime), A113189 (number of times that Fibonacci(n)-Fibonacci(i) is prime for i=0..n-3).

Sequence in context: A020588 A114111 A155108 this_sequence A079153 A020616 A067910

Adjacent sequences: A113185 A113186 A113187 this_sequence A113189 A113190 A113191

KEYWORD

nonn

AUTHOR

T. D. Noe (noe(AT)sspectra.com), Oct 17 2005

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Last modified December 8 08:31 EST 2009. Contains 170430 sequences.


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