OFFSET
1,1
COMMENTS
The primes correspond to indices m = 1, 43, 824747, 3171671, ... = A125828. - M. F. Hasler, Dec 01 2013
a(10) > 1352363608564489. - Bruce Garner, Jul 07 2021
FORMULA
a(n) = prime(A125828(n)). - M. F. Hasler, Dec 01 2013
EXAMPLE
a(2) = 191, because 191 is the 43rd prime and the sum of the first 43 primes^8 = 7287989395992721002 = 43 * 169488125488202814.
MATHEMATICA
t = {}; sm = 0; Do[sm = sm + Prime[n]^8; If[Mod[sm, n] == 0, AppendTo[t, Prime[n]]], {n, 100000}]; t (* Derived from A217599 *)
PROG
(PARI) is(n)=if(!isprime(n), return(0)); my(t=primepi(n), s); forprime(p=2, n, s+=Mod(p, t)^8); s==0 \\ Charles R Greathouse IV, Nov 30 2013
(PARI) S=n=0; forprime(p=1, , (S+=p^8)%n++||print1(p", ")) \\ M. F. Hasler, Dec 01 2013
KEYWORD
nonn,more
AUTHOR
Robert Price, Nov 30 2013
EXTENSIONS
a(5)-a(6) from Paul W. Dyson, Jan 01 2021
a(7) from Bruce Garner, Mar 02 2021
a(8) from Bruce Garner, Mar 30 2021
a(9) from Bruce Garner, Jul 07 2021
a(10) from Paul W. Dyson, Jul 07 2023
STATUS
approved