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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A100993 Indices n of Fibonacci numbers Fib(n) (A000045) that are divisible by n-1. 1
2, 3, 4, 8, 14, 18, 24, 38, 44, 48, 54, 68, 74, 84, 98, 104, 108, 114, 128, 138, 158, 164, 168, 174, 194, 198, 224, 228, 234, 258, 264, 278, 284, 294, 308, 314, 318, 324, 338, 348, 354, 368, 374, 378, 384, 398, 434, 444, 458, 464, 468, 488, 504, 524, 548, 558 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

When n-1 is prime, it is in A003631; when n-1 is composite (such as 323), it is in A069107. - T. D. Noe (noe(AT)sspectra.com), Dec 13 2004

LINKS

R. Knott Mathematical Magic of the Fibonacci Numbers

FORMULA

a(n) = A069104(n) + 1 - T. D. Noe (noe(AT)sspectra.com), Dec 13 2004

EXAMPLE

14 because F(14)=377=13*29 so is divisible by 13, one less than its index number 14.

MATHEMATICA

Select[Range[2, 500], Mod[ Fibonacci[ # ], # - 1] == 0 &] (from Robert G. Wilson v Nov 26 2004)

CROSSREFS

Cf. A100992, A023162, A023173.

Sequence in context: A091415 A166342 A091816 * A117395 A006755 A005853

Adjacent sequences:  A100990 A100991 A100992 * A100994 A100995 A100996

KEYWORD

nonn

AUTHOR

Ron Knott (fibandphi(AT)ronknott.com), Nov 25 2004

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 12 21:29 EST 2012. Contains 205433 sequences.