OFFSET
1,2
COMMENTS
We call a(n) the multiplicative index of odious-evil stability of 2*n-1.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
V. Shevelev, "Odious-evil stability" of integers
FORMULA
EXAMPLE
For n=2, t=2*n-1=3. We see that 3*1=3, 3*3=9,3*5=15 are evil, but 3*7=21 is odious. So, a(2)=3.
PROG
(PARI) a(n)=my(t=2*n-1, H=hammingweight(t)%2, i=3); while(H == hammingweight(i*t)%2, i+=2); i\2 \\ Charles R Greathouse IV, Oct 22 2013
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Oct 21 2013
EXTENSIONS
a(17)-a(87) from Charles R Greathouse IV, Oct 22 2013
STATUS
approved