A104260 -id:A104260 - cp's OEIS frontend

A104261 Sum of even digits (0,2,4,6,8) of n-th prime.

2, 0, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 4, 4, 4, 0, 0, 6, 6, 0, 0, 0, 8, 8, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 4, 0, 0, 6, 6, 0, 0, 8, 0, 0, 0, 0, 2, 4, 4, 4, 2, 2, 6, 2, 2, 8, 8, 2, 2, 10, 10, 2, 0, 0, 0, 0, 0, 0, 4, 4, 0, 0, 6, 0, 0, 8, 8, 0, 4, 4, 4, 6, 4, 4, 4, 8, 8, 4, 10, 10, 10, 4, 12, 4, 4, 0, 0, 2, 2, 4, 4, 0

Offset: 1

Zak Seidov, Feb 26 2005

Sum of odd digits (1, 3, 5, 7, 9) of n-th prime: A104260, sum of prime digits (2, 3, 5, 7) of n-th prime: A104250, sum of composite (nonprime) digits (1, 4, 6, 8, 9) of n-th prime: A104251, sum of digits of primes: A007605, primes: A000040.

sodev={};Do[id=IntegerDigits[Prime[i]];lid=Length[id];sod=Sum[If[EvenQ[id[[k]]], id[[k]], 0], {k, lid}];sodev={sodev, sod}, {i, 200}];sodev//Flatten
f[n_] := Plus @@ Select[ IntegerDigits[ Prime[n]], EvenQ[ # ] && # > 1 &]; Table[ f[n], {n, 102}] (* Robert G. Wilson v, Nov 03 2005 *)

A104261(n) = A007605(n) - A104260(n).

A226017 Primes such that sum of odd digits is also prime.

Original entry on oeis.org

3, 5, 7, 11, 23, 43, 47, 67, 83, 101, 113, 131, 137, 139, 151, 157, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 263, 283, 311, 313, 317, 331, 337, 353, 359, 373, 379, 397, 443, 463, 467, 487, 557, 571, 577, 593, 599, 607, 643, 647, 683, 719, 733, 739

Offset: 1

Jayanta Basu, May 23 2013

Primes such that A104260(n) is prime.

			181 is a member since sum of odd digits=2.

Cf. A071649, A104260.

soQ[n_]:=PrimeQ[Total[Select[IntegerDigits[n],OddQ[#] &]]]; Select[Prime[Range[132]],soQ[#] &]

cp's OEIS Frontend

A104261 Sum of even digits (0,2,4,6,8) of n-th prime.

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