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A222565
Primes that are the largest anti-divisor of primes.
5
2, 3, 5, 7, 11, 13, 19, 29, 31, 41, 47, 53, 59, 67, 71, 73, 101, 109, 127, 131, 149, 151, 167, 179, 181, 211, 233, 239, 281, 293, 307, 311, 347, 349, 379, 401, 409, 421, 431, 439, 449, 461, 467, 479, 541, 547, 569, 571, 587, 607, 613, 619, 631, 647, 661, 673, 701
OFFSET
1,1
COMMENTS
See A066272 for definition of anti-divisor.
Primes p such that 2p + largest anti-divisor of 2p is also prime: 2, 5, 7, 11, 13, 29, 31, 41, 47, 59, 67, 79, 83, 101, 137, 139, 151, 157, 167, 173, 193, 223, 227, 239, 257,...
LINKS
FORMULA
2 together with primes of the form 4k+1 such that 6k+1 is prime, together with primes of the form 4k+3 such that 6k+5 is prime. - Charles R Greathouse IV, Feb 27 2013
EXAMPLE
The prime 19 is here because it is largest anti-divisor of prime 29.
PROG
(PARI) is(n)=isprime(n)&&isprime(bitor((3*n-1)\2, 1)) \\ Charles R Greathouse IV, Feb 27 2013
CROSSREFS
Cf. A066481.
Sequence in context: A114111 A155108 A356856 * A113188 A358718 A242738
KEYWORD
nonn
AUTHOR
EXTENSIONS
Missing terms a(9), a(21), a(28), a(29) added by Charles R Greathouse IV, Feb 27 2013
STATUS
approved