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A233040 Prime(n), where n is such that (1 + Sum_{i=1..n} prime(i)^7) / n is an integer. 1
2, 3, 7, 11, 13, 29, 37, 199, 15679, 18211, 59359, 78203, 84533, 166399, 528299, 639697, 2080651, 2914033, 5687413, 73463179, 112760273, 156196991, 278840981, 503948113, 3706314893, 3786209711, 12626179519, 13551633533, 13844655553, 24074338279, 37937104823 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(43) > 458158058915101. - Bruce Garner, Apr 07 2021
LINKS
Bruce Garner, Table of n, a(n) for n = 1..42 (first 35 terms from Robert Price)
EXAMPLE
a(4) = 11, because 11 is the 5th prime and the sum of the first 5 primes^7+1 = 20391155 when divided by 5 equals 4078231, which is an integer.
MATHEMATICA
t = {}; sm = 1; Do[sm = sm + Prime[n]^7; 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)^7); s==0 \\ Charles R Greathouse IV, Nov 30 2013
CROSSREFS
Cf. A085450 = smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n.
Sequence in context: A233863 A371065 A233194 * A233769 A038895 A291657
KEYWORD
nonn
AUTHOR
Robert Price, Dec 03 2013
STATUS
approved

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Last modified August 20 22:00 EDT 2024. Contains 375340 sequences. (Running on oeis4.)