|
|
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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
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
|
|
|
PROG
|
(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..]
(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
(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
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy,base,nice
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|