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A250444 Numbers n such that gcd(n!, Fibonacci(n)) is prime. 2
3, 4, 5, 9, 10, 14, 33, 38, 39, 49, 51, 52, 55, 65, 69, 74, 77, 85, 87, 92, 93, 115, 119, 121, 123, 124, 129, 141, 143, 145, 155, 158, 159, 161, 172, 177, 183, 187, 188, 194, 201, 203, 205, 212, 213, 215, 217, 219, 235, 236, 244, 249, 253, 265, 267, 268, 278, 287, 292, 295, 299 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

For n = 3: GCD(3!, Fibonacci(3)) = 2.

For n = 4: GCD(4!, Fibonacci(4)) = 3.

For n = 9: GCD(9!, Fibonacci(9)) = 2.

MAPLE

select(n -> isprime(igcd(n!, combinat:-fibonacci(n))), [$1..1000]); # Robert Israel, Nov 24 2014

MATHEMATICA

Select[Range[300], PrimeQ[GCD[#!, Fibonacci[#]] ] &]

PROG

(PARI) for(n=1, 10^3, if(isprime(gcd(n!, fibonacci(n))), print1(n, ", "))) \\ Derek Orr, Nov 23 2014

CROSSREFS

Sequence in context: A236211 A279616 A050068 * A327178 A190211 A136120

Adjacent sequences:  A250441 A250442 A250443 * A250445 A250446 A250447

KEYWORD

nonn,easy

AUTHOR

Carlos Eduardo Olivieri, Nov 23 2014

STATUS

approved

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Last modified January 26 22:05 EST 2022. Contains 350601 sequences. (Running on oeis4.)