OFFSET
1,2
COMMENTS
All the terms of A112368 starting from a(72) are divisible by 73.
The first 9 associated primes are 3, 11, 59, 443, 4283, 50363, 85662309563, 1726380042510080613563, 4824162806180387282426469563. The 10th and last term is about 2.022... * 10^123.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10
EXAMPLE
1 is in this sequence because 2^0*0! + 2^1*1! = 3 is prime.
PROG
(PARI) isok(n) = isprime(sum(i=0, n, 2^i*i!)); \\ Michel Marcus, Mar 11 2017
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
Amiram Eldar, Mar 11 2017
STATUS
approved