|
|
A173473
|
|
n-th prime^2-2*n is prime.
|
|
2
|
|
|
1, 2, 3, 4, 6, 10, 15, 16, 19, 22, 24, 28, 31, 46, 48, 49, 61, 66, 70, 88, 90, 91, 93, 94, 96, 97, 111, 114, 118, 126, 130, 136, 141, 157, 159, 160, 163, 171, 177, 196, 199, 201, 210, 211, 213, 216, 225, 238, 243, 255, 258, 279, 294, 300, 306, 309, 312, 315, 324, 330
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
EXAMPLE
|
1 is in the sequence because (1st prime)^2-2*1=2, which is prime;
2 is in the sequence because (2nd prime)^2-2*2=5, which is prime.
|
|
MATHEMATICA
|
|
|
PROG
|
(PARI) isok(n) = isprime(prime(n)^2 - 2*n); \\ Michel Marcus, Apr 15 2014
(Magma) [n: n in [0..400] | IsPrime(NthPrime(n)^2-2*n)]; // Vincenzo Librandi, Apr 15 2014
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|