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A250445 a(n) = gcd(n!, Fibonacci(n)) as n runs through A250444. 1
2, 3, 5, 2, 5, 13, 2, 37, 2, 13, 2, 3, 5, 5, 2, 73, 13, 5, 2, 3, 2, 5, 13, 89, 2, 3, 2, 2, 89, 5, 5, 157, 2, 13, 3, 2, 2, 89, 3, 193, 2, 13, 5, 3, 2, 5, 13, 2, 5, 3, 3, 2, 89, 5, 2, 3, 277, 13, 3, 5, 233, 13, 2, 5, 2, 313, 89, 2, 2, 13, 3, 2, 89, 5, 5, 13, 233, 2, 2, 397, 233, 3, 2, 3, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

By the definition of A250444, all terms are prime.

LINKS

Table of n, a(n) for n=1..85.

EXAMPLE

For n = 9, GCD(9!, Fibonacci(9)) = 2, (prime, thus belongs to the sequence).

MATHEMATICA

a[n_] := GCD[n!, Fibonacci[n]];

p[n_] := Which[PrimeQ[a[n]], a[n], PrimeQ[a[n]] == False, ];

Select[Table[p[n], {n, 1, 300}], IntegerQ[#] &]

PROG

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

CROSSREFS

Cf. A000045, A000142, A250444.

Sequence in context: A102044 A125766 A093870 * A297996 A239692 A126833

Adjacent sequences:  A250442 A250443 A250444 * A250446 A250447 A250448

KEYWORD

nonn,easy

AUTHOR

Carlos Eduardo Olivieri, Nov 23 2014

EXTENSIONS

More terms from Derek Orr, Nov 23 2014

STATUS

approved

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Last modified January 22 10:13 EST 2022. Contains 350481 sequences. (Running on oeis4.)