login
n-th prime + n-th problime (third definition).
0

%I #8 Oct 20 2013 13:53:44

%S 4,7,12,18,26,32,40,47,56,67,74,85,94,101,110,121,132,140,152,162,170,

%T 182,192,204,218,228,236,246,254,264,284,294,306,314,330,338,350,362,

%U 372,384,396,405,422,431,442,451,470,489,500,509,520,533,542,559,572,585,598,607,620,631,640,657,678

%N n-th prime + n-th problime (third definition).

%C The partial sequence of values which are themselves primes begins: 7, 47, 101. The partial sequence of values which are themselves problimes (third definition) begins: 4, 7, 85, 121.

%F a(n) = A000040(n) + A003068(n).

%e a(10) = prime(10) + A003068(10) = 29 + 38 = 67 is prime.

%Y Cf. A000040, A003068, A100484.

%K nonn

%O 1,1

%A _Jonathan Vos Post_, Dec 29 2010

%E Corrected and extended. - _R. J. Mathar_, Oct 20 2013