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A095006 Number of evil primes (A027699) in range ]2^n,2^(n+1)]. 6
1, 1, 0, 3, 2, 5, 4, 23, 27, 62, 95, 222, 367, 777, 1269, 2910, 4859, 10140, 17714, 36714, 66020, 133400, 245959, 493532, 916913, 1822087, 3428633, 6782008, 12870735, 25339113, 48419194, 95194890, 182818705 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..33.

A. Karttunen and J. Moyer, C-program for computing the initial terms of this sequence

Index entries for sequences related to occurrences of various subsets of primes in range ]2^n,2^(n+1)]

EXAMPLE

From Michael De Vlieger, Feb 27 2017: (Start)

a(2) = 1 since between 2^2 and 2^3 only the prime 5 (binary 11) has an even number of 1s.

a(3) = 0 since none of the primes between 2^3 and 2^4 have an even number of 1s in their binary expansions.

a(4) = 3 since the primes 17, 23, and 29 have an even number of 1s in their binary expansions (i.e., 10001, 10111, 11101). (End)

MATHEMATICA

Table[m = Count[Prime@ Range[PrimePi[2^n] + 1, PrimePi[2^(n + 1) - 1]], k_ /; EvenQ@ DigitCount[k, 2, 1]]; Print@ m; m, {n, 24}] (* Michael De Vlieger, Feb 27 2017 *)

CROSSREFS

a(n) = A036378(n)-A095005(n).

Sequence in context: A120332 A302698 A205401 * A159587 A124732 A167552

Adjacent sequences:  A095003 A095004 A095005 * A095007 A095008 A095009

KEYWORD

nonn

AUTHOR

Antti Karttunen and Labos Elemer, Jun 01 2004

STATUS

approved

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Last modified June 26 10:12 EDT 2019. Contains 324375 sequences. (Running on oeis4.)