A336481 a(n) is the smallest positive k such that Fibonorial(n) - k is a prime, for n>3.

1, 1, 1, 1, 1, 11, 19, 19, 29, 19, 1, 1, 97, 41, 23, 131, 107, 53, 101, 529, 53, 269, 347, 97, 317, 97, 353, 73, 97, 193, 71, 1543, 661, 257, 193, 191, 151, 443, 167, 967, 251, 2441, 163, 151, 379, 229, 127, 59, 1223, 911, 389, 349, 919, 179, 1051, 167, 547, 541

Offset

4,6

Links

Table of n, a(n) for n=4..61.

Example

For n=5, a(5) = Fibonorial(5) - 1 = 30 - 1 = 29 is a prime.

Mathematica

Table[(Fibonorial[n]-NextPrime[Fibonorial[n], -1]), {n, 4, 50}]

Prog

(PARI) f(n) = prod(i=1, n, fibonacci(i)); \\ A003266
a(n) = my(fn=f(n)); fn - precprime(fn-1); \\ Michel Marcus, Jul 23 2020

Crossrefs

Cf. A003266, A059709 (locations of 1's), A336480.

Sequence in context: A123248 A341899 A306920 * A111477 A344936 A238247

Adjacent sequences: A336478 A336479 A336480 * A336482 A336483 A336484

Keyword

nonn

Author

Mohamed Sami Gattoufi, Jul 22 2020

Status

approved