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A232823 Numbers k such that k divides 1 + Sum_{j=1..k} (prime(j)^8). 1

%I #39 Mar 20 2022 04:22:20

%S 1,2,3,4,5,6,8,9,10,12,15,16,20,24,28,30,32,37,39,40,45,48,60,64,80,

%T 90,96,100,104,120,133,160,168,174,180,205,211,240,247,320,360,456,

%U 480,512,540,560,563,580,676,692,735,820,864,930,960,1215,1216,1368

%N Numbers k such that k divides 1 + Sum_{j=1..k} (prime(j)^8).

%C a(305) > 1.2*10^14. - _Bruce Garner_, Mar 20 2022

%H Bruce Garner, <a href="/A232823/b232823.txt">Table of n, a(n) for n = 1..304</a> (terms 1..227 from Robert Price)

%H OEIS Wiki, <a href="https://oeis.org/wiki/Sums_of_primes_divisibility_sequences">Sums of powers of primes divisibility sequences</a>

%e a(7)=8 because 1 plus the sum of the first 8 primes^8 is 24995572328 which is divisible by 8.

%t p = 2; k = 0; s = 1; lst = {}; While[k < 521330000, s = s + p^8; If[Mod[s, ++k] == 0, AppendTo[lst, k]; Print[{k, p}]]; p = NextPrime@ p](* Derived from A128169 *)

%Y Cf. A085450 (smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n).

%Y Cf. A007504, A045345, A171399, A128165, A233523, A050247, A050248.

%Y Cf. A024450, A111441, A217599, A128166, A233862, A217600, A217601.

%K nonn

%O 1,2

%A _Robert Price_, Nov 30 2013

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Last modified May 18 16:58 EDT 2024. Contains 372664 sequences. (Running on oeis4.)