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A168156
Sum of the binary digits of all primes between 2^(n-1) and 2^n-1, i.e., with exactly n binary digits.
2
0, 3, 5, 6, 18, 29, 56, 113, 240, 452, 885, 1790, 3474, 6951, 13671, 27183, 54201, 107224, 213882, 424513, 845716, 1682456, 3350362, 6671581, 13299828, 26500297, 52829961, 105342821, 210088965, 419106389, 836097752, 1668341390, 3329412989, 6645128078
OFFSET
1,2
COMMENTS
Sequence A168155 yields the partial sums.
EXAMPLE
No prime can be written with only 1 binary digit, thus a(1)=0.
The primes that can be written with 2 binary digits are 2 = 10[2] and 3 = 11[2], they have 3 nonzero bits, so a(2)=3.
Primes with 3 binary digits are 5 = 101[2] and 7 = 111[3]. They have a total of a(3)=5 nonzero bits.
PROG
(PARI) s=0; L=p=2; while( L*=2, print1(s", "); s=0; until( L<p=nextprime(p+1), s+=norml2(binary(p))))
(PARI) a(n)=my(s); forprime(p=2^(n-1), 2^n-1, s+=hammingweight(p)); s \\ Charles R Greathouse IV, Apr 07 2020
CROSSREFS
Cf. A086904.
Sequence in context: A192119 A050563 A282809 * A295403 A272440 A276704
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Nov 20 2009
EXTENSIONS
a(26)-a(32) from Donovan Johnson, Jul 28 2010
a(33) from Chai Wah Wu, Apr 06 2020
a(34) from Chai Wah Wu, Apr 07 2020
STATUS
approved