A104250 Sum of prime digits of n-th prime.

2, 3, 5, 7, 0, 3, 7, 0, 5, 2, 3, 10, 0, 3, 7, 8, 5, 0, 7, 7, 10, 7, 3, 0, 7, 0, 3, 7, 0, 3, 9, 3, 10, 3, 0, 5, 12, 3, 7, 10, 7, 0, 0, 3, 7, 0, 2, 7, 11, 4, 8, 5, 2, 7, 14, 5, 2, 9, 16, 2, 5, 5, 10, 3, 6, 10, 6, 13, 10, 3, 11, 8, 10, 13, 10, 6, 3, 10, 0, 0, 0, 2, 3, 6, 3, 3, 0, 12, 0, 3, 7, 7, 7, 0, 0, 8, 5

Offset: 1

Author

Zak Seidov, Feb 26 2005

Keywords

• nonn
• base

Examples

			a(6)=3 because sum of prime digits of Prime[6]=13 is 3.
		

Crossrefs

Sum of nonprime digits (1, 4, 6, 8, 9) of n-th prime: A104251. Primes A000040: sum of digits of primes: A007605.

Programs

Mathematica

npd[n_]:=Total[Select[IntegerDigits[n],PrimeQ]]; Table[npd[p],{p,Prime[ Range[100]]}] (* Harvey P. Dale, Apr 24 2014 *)

Formula

a(n)=A007605(n)-A104251(n)