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A143580 A143579 mod 2. +0
1
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0 (list; graph; listen)
OFFSET

0,1

COMMENT

Two conjectures: If n is even, the ratio of 1's to 0's = 1:1.

There are no three adjacent terms of the same parity.

Conjecture (verified for the first 280000 entries): this is the characteristic function of A001969 and therefore a duplicate of A010059. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 05 2008]

FORMULA

Parity of A143579 (Odious numbers interleaved with Evil numbers); A000069 = Odious numbers, A001969 = Evil numbers).

EXAMPLE

First few terms of A143579 = (1, 0, 2, 3, 4, 5, 7,...), mod 2 = (1, 0, 0, 1, 0, 1, 1,...).

MATHEMATICA

od = Select[ Range[0, 129], OddQ@ DigitCount[ #, 2, 1] &]; ev = Select[ Range[0, 129], EvenQ@ DigitCount[ #, 2, 1] &]; Mod[ Flatten@ Transpose[{od, ev}], 2] [From Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 14 2009]

CROSSREFS

Cf. A010060, A000069, A001969.

Sequence in context: A005171 A076404 A010059 this_sequence A011749 A104105 A143221

Adjacent sequences: A143577 A143578 A143579 this_sequence A143581 A143582 A143583

KEYWORD

nonn

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Aug 24 2008

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 14 2009

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Last modified December 16 13:01 EST 2009. Contains 170825 sequences.


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