A250444 - OEIS

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A250444

Numbers n such that gcd(n!, Fibonacci(n)) is prime.

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