

A144675


Numbers n such that A090831(n) is prime.


1




OFFSET

1,2


COMMENTS

No further terms up to n=2540 (A090831(2540) ~ 10^7400). A090831(242) is a proved prime (in spite of the given PARI code).
Obviously all terms beyond the first must be even, so one might as well consider a(n)/2 = 1,3,4,5,121,...


LINKS



PROG

(PARI) print1(1); forstep( n=2, 3000, 2, /* n%10print1([n]); */ ispseudoprime( sum( i=1, n, prime(i)^(n+1i))) & print1(", "n))


CROSSREFS



KEYWORD

nonn,more,hard


AUTHOR



STATUS

approved



