OFFSET
1,4
LINKS
FORMULA
MAPLE
f:= n -> add(n-2*i, i = select(t -> numtheory:-issqrfree(t)=numtheory:-issqrfree(n-t), [$1..n/2])):
map(f, [$1..100]); # Robert Israel, Jun 12 2020
MATHEMATICA
Table[Sum[(n - 2 k) KroneckerDelta[MoebiusMu[k]^2, MoebiusMu[ n - k]^2], {k, Floor[n/2]}], {n, 80}]
CROSSREFS
KEYWORD
AUTHOR
Wesley Ivan Hurt, Oct 22 2017
STATUS
approved