OFFSET
1,4
LINKS
MATHEMATICA
Table[Sum[(n - 2 i) (PrimePi[n - i] - PrimePi[n - i - 1]) MoebiusMu[i]^2, {i, Floor[n/2]}], {n, 80}]
Table[Total[#[[1]]-#[[2]]&/@Select[IntegerPartitions[n, {2}], PrimeQ[#[[1]]]&&SquareFreeQ[ #[[2]]]&]], {n, 70}] (* Harvey P. Dale, Jun 08 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Oct 22 2017
STATUS
approved