Number of numbers x such that primepi(n * x) = n + x.
22, 9, 15, 1, 13, 7, 8, 26, 21, 10
5
T. D. Noe, Plot of 10 terms
(Mma) Table[Length[Select[Range[1000000], PrimePi[n*#] == n + # &]], {n, 5, 14}]
Cf. A038626 (smallest value of pi(x) having n*pi(x) = x), S000263.
nonn,more
T. D. Noe, Sep 22 2014