|
|
A161367
|
|
Primes such that prime(k)-prime(k-1)+1 is not prime.
|
|
0
|
|
|
97, 127, 307, 331, 367, 397, 409, 457, 487, 499, 691, 709, 727, 751, 769, 787, 853, 877, 907, 919, 937, 967, 991, 1117, 1171, 1201, 1361, 1381, 1423, 1447, 1531, 1567, 1579, 1597, 1657, 1693, 1741, 1831, 1861, 1987, 2011, 2053, 2161, 2203, 2221, 2251, 2281, 2371, 2437, 2467
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
EXAMPLE
|
a(1)=97 because it is the first prime, prime(k), such that prime(k)-prime(k-1)+1 is not prime: 97-89+1=15, and 15 is not prime.
|
|
PROG
|
(PARI) isok(p) = isprime(p) && !isprime(p-precprime(p-1)+1); \\ Michel Marcus, May 12 2024
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|