OFFSET
1,6
FORMULA
a(n) = floor(sqrt(n-1)) + ((-1)^(n+floor(sqrt(n)))-1)/2.
EXAMPLE
a(3) = a(2-2*a(2))+1 = a(2)+1 = 1.
a(4) = a(3-2*a(3))+1 = a(1)+1 = 1.
a(5) = a(4-2*a(4))+1 = a(2)+1 = 1.
a(6) = a(5-2*a(5))+1 = a(3)+1 = 2.
MATHEMATICA
Table[Floor[Sqrt[n-1]] + ((-1)^(n+Floor[Sqrt[n]])-1)/2, {n, 87}] (* Stefano Spezia, Dec 29 2020 *)
PROG
(Python)
a = [0, 0]
for n in range(1, 1000):
a.append(a[n-2*a[n]]+1)
CROSSREFS
KEYWORD
nonn
AUTHOR
Rok Cestnik, Dec 29 2020
EXTENSIONS
More terms from Stefano Spezia, Dec 29 2020
STATUS
approved