OFFSET
1,1
COMMENTS
First differences are in {3, 4, 5}; 4*n - 2 <= a(n) <= 4*n. - Charles R Greathouse IV, Dec 26 2013
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
Total/@Partition[Select[Range[0, 200], EvenQ[DigitCount[#, 2, 1]]&], 2, 1] (* Harvey P. Dale, Nov 02 2015 *)
PROG
(PARI) a(n)=4*n+hammingweight(n-1)%2+hammingweight(n)%2-2 \\ Charles R Greathouse IV, Dec 26 2013
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Irina Gerasimova, Dec 26 2013
STATUS
approved