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A100993 Indices n of Fibonacci numbers Fib(n) (A000045) that are divisible by n-1. 2
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; text; 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, Dec 13 2004

LINKS

Table of n, a(n) for n=1..56.

Ron Knott Mathematical Magic of the Fibonacci Numbers

FORMULA

a(n) = A069104(n) + 1. - T. D. Noe, 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 &] (* Robert G. Wilson v, Nov 26 2004 *)

CROSSREFS

Cf. A100992, A023162, A023173.

Sequence in context: A091816 A266400 A274914 * A117395 A006755 A005853

Adjacent sequences:  A100990 A100991 A100992 * A100994 A100995 A100996

KEYWORD

nonn

AUTHOR

Ron Knott, Nov 25 2004

STATUS

approved

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Last modified September 25 12:53 EDT 2017. Contains 292469 sequences.