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A104261
Sum of even digits (0,2,4,6,8) of n-th prime.
2
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
1,1
FORMULA
A104261(n) = A007605(n) - A104260(n).
MATHEMATICA
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 *)
CROSSREFS
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.
Sequence in context: A280799 A355860 A374089 * A028702 A083929 A182660
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Feb 26 2005
STATUS
approved