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A125828 Numbers m that divide 2^8 + 3^8 + ... + prime(m)^8. 4
1, 43, 824747, 3171671, 767335408183, 921649796621, 1367268373487, 8978321374181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No other terms up to 10^8. - Stefan Steinerberger, Jun 06 2007

No other terms up to pi(10^13). - Charles R Greathouse IV, Apr 14 2011

a(9) > 9*10^12. - Bruce Garner, Mar 30 2021

LINKS

Table of n, a(n) for n=1..8.

OEIS Wiki, Sums of powers of primes divisibility sequences.

FORMULA

A125828 = A000720 o A232822, i.e., a(n)=PrimePi(A232822(n)). - M. F. Hasler, Dec 01 2013

MATHEMATICA

s = 0; t = {}; Do[s = s + Prime[n]^8; If[ Mod[s, n] == 0, AppendTo[t, n]], {n, 1000000}]; t

PROG

(PARI) S=n=0; forprime(p=1, , (S+=p^8)%n++||print1(n", ")) \\ M. F. Hasler, Dec 01 2013

CROSSREFS

Sequence in context: A212738 A291993 A228546 * A177417 A116139 A087529

Adjacent sequences:  A125825 A125826 A125827 * A125829 A125830 A125831

KEYWORD

nonn,hard,more

AUTHOR

Alexander Adamchuk, Feb 03 2007

EXTENSIONS

a(4) from Stefan Steinerberger, Jun 06 2007

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

STATUS

approved

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Last modified May 14 19:53 EDT 2021. Contains 343903 sequences. (Running on oeis4.)