login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A233768 Numbers n such that n divides 1 + sum_{k=1,n} prime(k)^19. 0
1, 2, 4, 5, 6, 10, 12, 53, 226, 361, 400, 620, 935, 1037, 3832, 3960, 4956, 7222, 12183, 13615, 24437, 80849, 450827, 680044, 7388490, 23503578, 27723887, 52048944, 85860268, 126177976, 606788411, 613917734, 2693408896, 3856356590, 5167833600, 5810025660, 9197308014, 10805855623, 19751202045, 19781610414, 27240188169, 30742119459 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(43) > 4*10^10.

LINKS

Table of n, a(n) for n=1..42.

OEIS Wiki, Sums of powers of primes divisibility sequences

EXAMPLE

a(5)=6 because 1 plus the sum of the first 6 primes^19 is 1523090798793695143992 which is divisible by 6.

MATHEMATICA

p = 2; k = 0; s = 1; lst = {}; While[k < 40000000000, s = s + p^19; If[Mod[s, ++k] == 0, AppendTo[lst, k]; Print[{k, p}]]; p = NextPrime@ p] (* derived from A128169 *)

CROSSREFS

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

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

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

Sequence in context: A177911 A127092 A128171 * A240748 A171165 A039036

Adjacent sequences:  A233765 A233766 A233767 * A233769 A233770 A233771

KEYWORD

nonn

AUTHOR

Robert Price, Dec 15 2013

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified July 23 09:03 EDT 2017. Contains 289686 sequences.