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A059847
a(n)=2*p+2n-1, the smallest prime q such that p=[q-(2n-1)]/2 is prime. A special generalization of safe primes: 1 is replaced with 2n-1.
1
5, 17, 67, 149, 127, 673, 1151, 541, 1399, 1973, 2203, 4201, 2999, 4861, 5623, 20477, 10007, 12889, 25523, 19661, 34123, 58889, 25523, 40693, 40343, 35729, 106087, 107441, 34123, 134581, 302399, 212777, 259099, 370373, 156007, 507289, 371027
OFFSET
1,1
FORMULA
Min{p|p and q=(p-2n+1)/2, p and q are primes}
EXAMPLE
n=8, 2n-1=15, a(8)=541 because (541-15)/2=263 is the corresponding generalized Sophie Germain prime and {541,263} is the smallest pair belonging to 15.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Feb 26 2001
STATUS
approved