OFFSET
1,1
COMMENTS
Let f(m) be the distance to the nearest prime as defined in A051699(m). Then a(n) = min { m: f(m)= 2n }. A051728 uses A051700(m) to define the distance.
Note that the requirement f(m)>=2n yields the same sequence as f(m)=2n here. (Reasoning: We are essentially probing for prime gaps of size 4n or larger while increasing m. One cannot get earlier hits by relaxing the requirement from the equal to the larger-or-equal sign, because m triggers as soon as the distance to the start of the gap reaches 2n, with both definitions. This is an inherent consequence of using A051699.)
FORMULA
a(n) = min {m : A051699(m) = 2n}.
MAPLE
CROSSREFS
KEYWORD
nonn
AUTHOR
R. J. Mathar, Nov 18 2007, Nov 30 2007
STATUS
approved