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A368642
a(n) = Sum_{k=1..n} mu(k)^2 * ceiling(n/k), where mu is the Möbius function (A008683).
1
1, 3, 6, 8, 11, 14, 19, 21, 23, 26, 31, 33, 38, 41, 46, 50, 53, 55, 60, 62, 67, 72, 77, 79, 83, 86, 90, 92, 97, 100, 109, 111, 114, 119, 124, 128, 133, 136, 141, 145, 150, 153, 162, 164, 168, 173, 178, 180, 184, 186, 191, 195, 200, 202, 207, 211, 216, 221, 226, 228
OFFSET
1,2
FORMULA
a(n) = A013928(n) + A008966(n) + A064608(n) - A034444(n).
MATHEMATICA
Table[Sum[MoebiusMu[k]^2*Ceiling[n/k], {k, n}], {n, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Jan 01 2024
STATUS
approved