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A059010
Natural numbers having an even number of nonleading zeros in their binary expansion.
10
1, 3, 4, 7, 9, 10, 12, 15, 16, 19, 21, 22, 25, 26, 28, 31, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60, 63, 64, 67, 69, 70, 73, 74, 76, 79, 81, 82, 84, 87, 88, 91, 93, 94, 97, 98, 100, 103, 104, 107, 109, 110, 112, 115, 117, 118, 121, 122, 124, 127, 129, 130
OFFSET
0,2
COMMENTS
Positions of ones in A298952, and of zeros in A059448. - John Keith, Mar 09 2022
LINKS
Indranil Ghosh, Table of n, a(n) for n = 0..25000 (terms 0..1000 from T. D. Noe)
Jean Paul Allouche, Jeffrey Shallit, and Guentcho Skordev, Self-generating sets, integers with missing blocks and substitutions, Discrete Math. 292 (2005) 1-15.
Clark Kimberling, Affinely recursive sets and orderings of languages, Discrete Math., 274 (2004), 147-160. [From N. J. A. Sloane, Jan 31 2012]
Jeffrey Shallit, Additive Number Theory via Automata and Logic, arXiv:2112.13627 [math.NT], 2021.
Wadim Zudilin, A strange identity of an MF (Mahler function), arXiv:2403.13604 [math.NT], 2024.
FORMULA
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
MATHEMATICA
Select[Range[130], EvenQ @ DigitCount[#, 2, 0] &] (* Jean-François Alcover, Apr 11 2011 *)
PROG
(PARI) is(n)=hammingweight(bitneg(n, #binary(n)))%2==0 \\ Charles R Greathouse IV, Mar 26 2013
(PARI) a(n) = if(n==0, 1, 2*n + (logint(n, 2) - hammingweight(n)) % 2); \\ Kevin Ryde, Mar 11 2021
(Haskell)
a059010 n = a059010_list !! (n-1)
a059010_list = filter (even . a023416) [1..]
-- Reinhard Zumkeller, Jan 21 2014
(Python)
#Program to generate the b-file
i=1
j=0
while j<=250:
if bin(i)[2:].count("0")%2==0:
print(str(j)+" "+str(i))
j+=1
i+=1 # Indranil Ghosh, Feb 03 2017
(R)
maxrow <- 4 # by choice
onezeros <- 1
for(m in 1:(maxrow+1)){
row <- onezeros[2^(m-1):(2^m-1)]
onezeros <- c(onezeros, c(1-row, row) )
}
a <- which(onezeros == 1)
a
# Yosu Yurramendi, Mar 28 2017
CROSSREFS
Cf. A059009 (complement).
Cf. A023416 (number of 0-bits), A059448 (their parity), A298952 (opposite parity).
Cf. A001969 (even 1-bits), A059012 (even both 0's and 1's), A059014 (even 0's, odd 1's).
Sequence in context: A263488 A344416 A330178 * A066928 A032726 A029739
KEYWORD
nonn,easy,base,nice
AUTHOR
Patrick De Geest, Dec 15 2000
EXTENSIONS
Name clarified by Antti Karttunen, Mar 28 2017
STATUS
approved