OFFSET
1,2
COMMENTS
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..10000
FORMULA
MATHEMATICA
Accumulate[Table[Boole[Max[FactorInteger[n][[;; , 2]]] < 4], {n, 1, 100}]] (* Amiram Eldar, Aug 10 2024 *)
PROG
(Python)
from sympy import mobius, integer_nthroot
def A375245(n): return int(sum(mobius(k)*(n//k**4) for k in range(1, integer_nthroot(n, 4)[0]+1)))
(PARI) a(n) = sum(d=1, sqrtnint(n, 4), moebius(d)*(n\d^4)) \\ Andrew Howroyd, Aug 10 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Chai Wah Wu, Aug 07 2024
EXTENSIONS
a(68) onwards from Andrew Howroyd, Aug 10 2024
STATUS
approved