login
a(n) = If[Floor[2*Mod[(Prime[n + 1] - Prime[n])*PrimePi[n]/n, 8]] == 7, Prime[n]]
0

%I #2 Mar 30 2012 17:34:19

%S 199,211,317,1381,1759,1913,2161,2503

%N a(n) = If[Floor[2*Mod[(Prime[n + 1] - Prime[n])*PrimePi[n]/n, 8]] == 7, Prime[n]]

%t a = Flatten[Table[If[Floor[2*Mod[(Prime[n + 1] - Prime[n])*PrimePi[n]/n, 8]] == 7, Prime[n], {}], {n, 1, 400}]]

%Y Cf. A001359.

%K nonn

%O 0,1

%A _Roger L. Bagula_, Jun 27 2005