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A181091 a(n) = Carmichael(F(n)), where F(n) are the Fibonacci numbers. 1
1, 1, 1, 2, 4, 2, 12, 6, 16, 20, 88, 12, 232, 84, 60, 138, 1596, 144, 1008, 40, 420, 792, 28656, 264, 3000, 15080, 5616, 840, 514228, 60, 335824, 152214, 19800, 135660, 141960, 7632, 13320, 785232, 135720, 2160, 1009256, 420, 433494436, 94248 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

The Carmichael function is defined as the smallest integer m such that k^m == 1 mod n for all k relatively prime to n.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

FORMULA

a(n) = A002997(A000045(n)). [From Jonathan Vos Post, Oct 02 2010]

EXAMPLE

a(5) = 4 is in the sequence because Fibonacci(5) = 5, k^4 ==1 mod 5 for k = 1,2,3,4 ;

a(7) = 12 is in the sequence because Fibonacci(7) = 13, k^12 ==1 mod 7 for k = 1,2,3,4,5,6.

MATHEMATICA

Table[Plus@@(Transpose[CarmichaelLambda[Fibonacci[n]]][[1]]), {n, 50}]

PROG

(MAGMA) [1, 1] cat [CarmichaelLambda(Fibonacci(n)) : n in [3..60]]; // Vincenzo Librandi, Aug 15 2016

CROSSREFS

Cf. A002997

Cf. A000045. [From Jonathan Vos Post, Oct 02 2010]

Sequence in context: A118921 A121799 A078034 * A161795 A138770 A006018

Adjacent sequences:  A181088 A181089 A181090 * A181092 A181093 A181094

KEYWORD

nonn

AUTHOR

Michel Lagneau, Oct 02 2010

STATUS

approved

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Last modified November 22 10:59 EST 2019. Contains 329389 sequences. (Running on oeis4.)