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A091785 Evil numbers (see A001969) in A003159. 7
3, 5, 9, 12, 15, 17, 20, 23, 27, 29, 33, 36, 39, 43, 45, 48, 51, 53, 57, 60, 63, 65, 68, 71, 75, 77, 80, 83, 85, 89, 92, 95, 99, 101, 105, 108, 111, 113, 116, 119, 123, 125, 129, 132, 135, 139, 141, 144, 147, 149, 153, 156, 159, 163, 165, 169, 172, 175, 177, 180, 183 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also n such that A033485(n) == 3 (mod 4); see A007413.

Also n such that A029883(n-1) = -1, A036577(n-1) = 0, A036585(n-1) = 1. - Philippe Deléham, Mar 25 2004

The number of odd numbers before the n-th even number in this sequence is a(n). - Philippe Deléham, Mar 27 2004

Numbers n such that {A010060(n-1), A010060(n)}={1,0} where A010060 is the Thue-Morse sequence. - Benoit Cloitre, Jun 16 2006

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

Aviezri S. Fraenkel, The vile, dopey, evil and odious game players, Discrete Math. 312 (2012), pp. 42-46.

Index entries for 2-automatic sequences.

FORMULA

a(n) = A003159(2*n) = A036554(2*n)/2.

a(n) is asymptotic to 3*n. - Benoit Cloitre, Mar 22 2004

A050292(a(n)) = 2n. - Philippe Deléham, Mar 26 2004

MATHEMATICA

A036554 := Select[Range[750], OddQ[IntegerExponent[#, 2]] &]; Table[ A036554[[2*n]]/2, {n, 1, 50}] (* G. C. Greubel, Jan 14 2018 *)

PROG

(PARI) is(n)=hammingweight(n-1)%2 && hammingweight(n)%2==0 \\ Charles R Greathouse IV, Mar 26 2013

CROSSREFS

Sequence in context: A020946 A304525 A310039 * A191403 A233779 A287105

Adjacent sequences:  A091782 A091783 A091784 * A091786 A091787 A091788

KEYWORD

easy,nonn

AUTHOR

Philippe Deléham, Mar 16 2004

EXTENSIONS

More terms from Benoit Cloitre, Mar 22 2004

STATUS

approved

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Last modified August 10 02:26 EDT 2020. Contains 336367 sequences. (Running on oeis4.)