login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A001602 Fibonacci entry points: a(n) = smallest m > 0 such that the n-th prime divides Fibonacci(m).
(Formerly M2310 N0912)
19
3, 4, 5, 8, 10, 7, 9, 18, 24, 14, 30, 19, 20, 44, 16, 27, 58, 15, 68, 70, 37, 78, 84, 11, 49, 50, 104, 36, 27, 19, 128, 130, 69, 46, 37, 50, 79, 164, 168, 87, 178, 90, 190, 97, 99, 22, 42, 224, 228, 114, 13, 238, 120, 250, 129, 88, 67, 270, 139, 28, 284, 147, 44, 310 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

"[a(n)] is called by Lucas the rank of apparition of p and we know it is a divisor of, or equal to p-1 or p+1" - Vajda, p. 84. [Note that a(5)=5. This is the only exception. - Chris Caldwell, Nov 03 2008]

Every number except 1, 2, 6 and 12 eventually occurs in this sequence. The number of times n occurs is A086597(n), the number of primitive prime factors of Fibonacci(n). - T. D. Noe, Jun 13 2008

REFERENCES

A. Brousseau, Fibonacci and Related Number Theoretic Tables. Fibonacci Association, San Jose, CA, 1972, p. 25.

D. E. Daykin and L. A. G. Dresel, Fibonacci Quarterly, vol 7 (1969), pages 23 - 30 and 82.

Ramon Glez-Regueral, An entry-point algorithm for high-speed factorization, Thirteenth Internat. Conf. Fibonacci Numbers Applications, Patras, Greece, 2008.

D. Jarden, Recurring Sequences. Riveon Lematematika, Jerusalem, 1966.

D. Lind et al., Tables of Fibonacci entry points, part 2, reviewed in Math. Comp., 20 (1966), 618-619.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

S. Vajda, Fibonacci and Lucas numbers and the Golden Section, Ellis Horwood Ltd., Chichester, 1989.

M. Wunderlich, Tables of Fibonacci entry points, reviewed in Math. Comp., 20 (1966), 618-619.

LINKS

T. D. Noe, Table of n, a(n) for n=1..10000

FORMULA

a(n) <= prime(n)^2. [Charles R Greathouse IV, Jul 31 2011]

EXAMPLE

The 5th prime is 11 and 11 first divides Fib(10)=55, so a(5) = 10.

CROSSREFS

Cf. A051694, A001177.

Sequence in context: A050590 A066906 A125884 * A087012 A047366 A184776

Adjacent sequences:  A001599 A001600 A001601 * A001603 A001604 A001605

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Jud McCranie (JudMcCranie(AT)ugaalum.uga.edu)

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 13 04:08 EST 2012. Contains 205435 sequences.