OFFSET
0,2
COMMENTS
LINKS
Index entries for linear recurrences with constant coefficients, signature (4, 1, -4).
FORMULA
a(n) = ceiling(4^n/15) + (n mod 2).
MATHEMATICA
a[n_] = Ceiling[4^n/15] + Boole[Mod[n, 2]==1]; Array[a, 24]
PROG
(PARI) a(n) = ceil(4^n/15)+(Mod(n, 2)==1);
(Python)
def A365103(n): return len({pow(x, 4, 1<<(n<<1)) for x in range(1<<(n<<1))}) # Chai Wah Wu, Sep 18 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Albert Mukovskiy, Aug 24 2023
STATUS
approved