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A105409
Numbers k such that prime(k)-2 and prime(k+2)-2 are both primes.
6
4, 6, 27, 34, 42, 44, 82, 141, 143, 172, 177, 235, 287, 295, 314, 319, 429, 459, 474, 476, 485, 578, 580, 585, 672, 744, 773, 863, 871, 873, 892, 935, 958, 1031, 1116, 1166, 1168, 1170, 1231, 1340, 1352, 1405, 1463, 1549, 1622, 1652, 1708, 1824, 1834, 1868
OFFSET
1,1
LINKS
PROG
(PARI) pnpk(n, m=2, k=2) = { local(x, v1, v2); for(x=1, n, v1 = prime(x)-k; v2 = prime(x+m)-k; if(isprime(v1)&isprime(v2), print1(x, ", ") ) ) ; } \\ corrected by Amiram Eldar, Oct 04 2024
(PARI) lista(pmax) = {my(k = 1, p = primes(4)); forprime(p1 = p[#p], pmax, k++; p[#p] = p1; if(p[2]- p[1] == 2 && p[4] - p[3] == 2, print1(k, ", ")); for(i = 1, #p-1, p[i] = p[i+1])); } \\ Amiram Eldar, Oct 04 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Cino Hilliard, May 01 2005
EXTENSIONS
Offset corrected by Amiram Eldar, Oct 04 2024
STATUS
approved