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A209611
Primes p(n) such that p(n)*(p(n+1)-p(n)) <= 2^(p(n+1)-p(n)).
0
2, 113, 199, 211, 293, 317, 523, 773, 839, 863, 887, 953, 1069, 1129, 1259, 1327, 1381, 1637, 1669, 1759, 1831, 1913, 1933, 1951, 2113, 2161, 2179, 2221, 2251, 2311, 2477, 2503, 2557, 2593, 2803, 2861, 2971, 3089, 3121, 3137, 3229, 3271, 3373, 3391, 3413, 3433
OFFSET
1,1
COMMENTS
Primes prime(n) which multiplied by the associated prime gap g=A001223(n) remain <= 2^g.
EXAMPLE
2 is in the sequence because 2*(3-2) = 2^(3-2), 113 is in the sequence because 113*(127-113) < 2^(127-113).
PROG
(PARI) isA209611(p)={
local(q=nextprime(p+1)-p) ;
return(isprime(p) && p*q <= 2^q) ; }
{
forprime(p=2, 3100, if(isA209611(p), print1(p" ") ) ; ) ;
} /* R. J. Mathar, Mar 19 2012 */
CROSSREFS
Sequence in context: A165975 A051590 A091302 * A042567 A142112 A285145
KEYWORD
nonn
AUTHOR
Gerasimov Sergey, Mar 10 2012
STATUS
approved