Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #70 Mar 23 2024 20:03:08
%S 1,3,4,7,9,10,12,15,16,19,21,22,25,26,28,31,33,34,36,39,40,43,45,46,
%T 48,51,53,54,57,58,60,63,64,67,69,70,73,74,76,79,81,82,84,87,88,91,93,
%U 94,97,98,100,103,104,107,109,110,112,115,117,118,121,122,124,127,129,130
%N Natural numbers having an even number of nonleading zeros in their binary expansion.
%C Positions of ones in A298952, and of zeros in A059448. - _John Keith_, Mar 09 2022
%H Indranil Ghosh, <a href="/A059010/b059010.txt">Table of n, a(n) for n = 0..25000</a> (terms 0..1000 from T. D. Noe)
%H Jean Paul Allouche, Jeffrey Shallit, and Guentcho Skordev, <a href="http://dx.doi.org/10.1016/j.disc.2004.12.004">Self-generating sets, integers with missing blocks and substitutions</a>, Discrete Math. 292 (2005) 1-15.
%H Clark Kimberling, <a href="http://dx.doi.org/10.1016/S0012-365X(03)00085-2">Affinely recursive sets and orderings of languages</a>, Discrete Math., 274 (2004), 147-160. [From _N. J. A. Sloane_, Jan 31 2012]
%H Jeffrey Shallit, <a href="https://arxiv.org/abs/2112.13627">Additive Number Theory via Automata and Logic</a>, arXiv:2112.13627 [math.NT], 2021.
%H Wadim Zudilin, <a href="https://arxiv.org/abs/2403.13604">A strange identity of an MF (Mahler function)</a>, arXiv:2403.13604 [math.NT], 2024.
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F a(0) = 1, a(2n) = -a(n) + 6n + 1, a(2n+1) = a(n) + 2n + 2. a(n) = 2n+1 - 1/2(1-(-1)^A023416(n)) = 2n+1 - A059448(n). - _Ralf Stephan_, Sep 17 2003
%t Select[Range[130], EvenQ @ DigitCount[#, 2, 0] &] (* _Jean-François Alcover_, Apr 11 2011 *)
%o (PARI) is(n)=hammingweight(bitneg(n,#binary(n)))%2==0 \\ _Charles R Greathouse IV_, Mar 26 2013
%o (PARI) a(n) = if(n==0,1, 2*n + (logint(n,2) - hammingweight(n)) % 2); \\ _Kevin Ryde_, Mar 11 2021
%o (Haskell)
%o a059010 n = a059010_list !! (n-1)
%o a059010_list = filter (even . a023416) [1..]
%o -- _Reinhard Zumkeller_, Jan 21 2014
%o (Python)
%o #Program to generate the b-file
%o i=1
%o j=0
%o while j<=250:
%o if bin(i)[2:].count("0")%2==0:
%o print(str(j)+" "+str(i))
%o j+=1
%o i+=1 # _Indranil Ghosh_, Feb 03 2017
%o (R)
%o maxrow <- 4 # by choice
%o onezeros <- 1
%o for(m in 1:(maxrow+1)){
%o row <- onezeros[2^(m-1):(2^m-1)]
%o onezeros <- c(onezeros, c(1-row, row) )
%o }
%o a <- which(onezeros == 1)
%o a
%o # _Yosu Yurramendi_, Mar 28 2017
%Y Cf. A059009 (complement).
%Y Cf. A023416 (number of 0-bits), A059448 (their parity), A298952 (opposite parity).
%Y Cf. A001969 (even 1-bits), A059012 (even both 0's and 1's), A059014 (even 0's, odd 1's).
%K nonn,easy,base,nice
%O 0,2
%A _Patrick De Geest_, Dec 15 2000
%E Name clarified by _Antti Karttunen_, Mar 28 2017