login
Sum of nonprime digits of n-th prime.
3

%I #7 Nov 21 2019 04:04:31

%S 0,0,0,0,2,1,1,10,0,9,1,0,5,4,4,0,9,7,6,1,0,9,8,17,9,2,1,1,10,2,1,2,1,

%T 10,14,2,1,7,7,1,10,10,11,10,10,19,2,0,0,9,0,9,5,1,0,6,15,1,0,9,8,9,0,

%U 2,1,1,1,0,4,13,0,9,6,0,9,8,17,9,5,13,14,5,5,4,13,8,17,4,11,10,10,13,12

%N Sum of nonprime digits of n-th prime.

%F a(n) = A007605(n) - A104250(n).

%e a(6)=1 because sum of composite (nonprime) digits of prime(6)=13 is 1.

%Y Cf. A000040 (primes).

%Y Cf. A007605 (sum of digits of primes), A104250 (sum of prime digits of n-th prime).

%K nonn,base

%O 1,5

%A _Zak Seidov_, Feb 26 2005