A091785 Evil numbers (see A001969) in A003159.

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

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: A352596 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