OFFSET
0,4
COMMENTS
Counting numbers appear at positions indexed by the evil numbers A001969, 0 otherwise.
LINKS
Amiram Eldar, Table of n, a(n) for n = 0..10000
FORMULA
MATHEMATICA
a[n_] := (1 + Floor[n/2])*(1 + (-1)^DigitCount[n, 2, 1])/2; Array[a, 100, 0] (* Amiram Eldar, Jul 22 2023 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Paul Barry, Jan 06 2005
STATUS
approved