OFFSET
1,3
COMMENTS
Partial sums of A104638. [R. J. Mathar, Feb 13 2009]
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
If n=1, concatenate first 1 prime = 2, then number of odd digits = 0 = a(1).
If n=2, concatenate first 2 primes = 23, then number of odd digits = 1 = a(2).
If n=3, concatenate first 3 primes = 235, then number of odd digits = 2 = a(3).
MAPLE
ListTools:-PartialSums([seq(nops(select(type, convert(ithprime(i), base, 10), odd)), i=1..100)]); # Robert Israel, Jul 15 2018
PROG
(PARI) a(n) = sum(k=1, n, #select(x->(x%2), digits(prime(k)))); \\ Michel Marcus, Jul 16 2018
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Juri-Stepan Gerasimov, Jan 23 2009
EXTENSIONS
Replaced 53 by 55. R. J. Mathar, Feb 13 2009
STATUS
approved