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A095005 Number of odious primes (A027697) in range ]2^n,2^(n+1)]. 6
0, 1, 2, 2, 5, 8, 19, 20, 48, 75, 160, 242, 505, 835, 1761, 2799, 5890, 10250, 20921, 36872, 74316, 134816, 267749, 492286, 977207, 1823657, 3598657, 6779899, 13336543, 25358424, 49763462, 95140695, 186504600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

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)]

FORMULA

a(n) = A036378(n)-A095006(n).

MATHEMATICA

Table[Count[Prime@ Range[PrimePi[2^n] + 1, PrimePi[2^(n + 1) - 1]], k_ /; OddQ@ First@ DigitCount[k, 2]], {n, 24}] (* Michael De Vlieger, Feb 25 2017 *)

PROG

(PARI) a(n) = #select(x->((hammingweight(x)%2)==1), primes([2^n+1, 2^(n+1)])); \\ Michel Marcus, Feb 26 2017

CROSSREFS

Cf. A036378, A095006.

Sequence in context: A005834 A052531 A257517 * A209066 A208938 A019086

Adjacent sequences:  A095002 A095003 A095004 * A095006 A095007 A095008

KEYWORD

nonn

AUTHOR

Antti Karttunen and Labos Elemer, Jun 01 2004

STATUS

approved

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Last modified December 14 04:53 EST 2018. Contains 318090 sequences. (Running on oeis4.)