OFFSET
1,1
COMMENTS
FORMULA
a(n) = PrimePi[ A122516[n] ].
EXAMPLE
MATHEMATICA
PrimePi[Flatten[Table[If[PrimeQ[Sum[ PrimePi[n], {n, 1, m}]], Sum[PrimePi[n], {n, 1, m}], {}], {m, 1, 500}]]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Sep 20 2006
EXTENSIONS
Edited by Robert G. Wilson v, Sep 28 2006
STATUS
approved