|
| |
|
|
A101997
|
|
Primes of the form 16*k-1 such that 4*k-1, 8*k-1, 32*k-1 and 64*k-1 are also primes.
|
|
8
|
|
|
|
719, 214559, 253679, 507359, 508559, 1017119, 1184399, 1363679, 2429279, 3242159, 4276799, 4490639, 6394799, 6486479, 7283999, 7464959, 7650719, 7683839, 8181359, 8553599, 8631599, 8981279, 9112319, 9428879, 10671119
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
|
|
|
FORMULA
|
|
|
|
EXAMPLE
|
4*45-1 = 179, 8*45-1 = 359, 16*45-1 = 719, 32*45-1 = 1439 and 64*45-1 = 2879 are primes, so 719 is a term.
|
|
|
MATHEMATICA
|
Select[With[{c=2^Range[2, 6]}, Table[c n-1, {n, 700000}]], AllTrue[#, PrimeQ]&][[All, 3]] (* Harvey P. Dale, Nov 29 2018 *)
|
|
|
PROG
|
(PARI) is(k) = if(k % 16 == 15, my(m = k\16 + 1); isprime(4*m-1) && isprime(8*m-1) && isprime(16*m-1) && isprime(32*m-1) && isprime(64*m-1), 0); \\ Amiram Eldar, May 13 2024
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
easy,nonn
|
|
|
AUTHOR
|
Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 23 2004
|
|
|
STATUS
|
approved
|
| |
|
|
