OFFSET
1,1
COMMENTS
It seems that lim_{n->oo} a(n)/n = 9/2. [This is true. The asymptotic density of this sequence is 2/9. - Amiram Eldar, Jan 16 2022]
Positions of -1 in the expansion of Sum_{k>=0} x^2^k/(1+x^2^k+x^2^(k+1)) (A084091).
LINKS
MATHEMATICA
Select[3 * Range[0, 81] + 2, EvenQ[IntegerExponent[#, 2]] &] (* Amiram Eldar, Jan 16 2022 *)
PROG
(PARI) for(n=0, 300, if(valuation(n, 2)%2==0&&n%3==2, print1(n", ")))
(Python)
from itertools import count, islice
def A084088_gen(): # generator of terms
return filter(lambda n:(n&-n).bit_length()&1, count(2, 3))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ralf Stephan, May 11 2003
STATUS
approved