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- Odd-bit primes ratio 2 answers

While working on a completely different (combinatorial) problem, I ran a simple program to calculate the parity of the first ~50000 primes (number of 1s in their binary representation modulo 2). The following graph summarizes the result:

The number of primes having even parity seems to grow slower.

Is there a math explanation ?

I looked to the correspoding OEIS entry, but it doesn't provide any detail.