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A294242
Number of partitions of 2n into two parts with the larger part nonsquarefree.
17
0, 0, 1, 1, 2, 2, 3, 3, 3, 3, 4, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 9, 9, 10, 10, 11, 11, 11, 11, 12, 13, 13, 13, 14, 14, 14, 15, 16, 16, 17, 17, 18, 18, 18, 18, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 22, 22, 23, 23, 25, 25, 25, 25, 26, 27, 27, 27, 28
OFFSET
1,5
FORMULA
a(n) = Sum_{i=1..n} (1 - mu(2*n-i)^2), where mu is the Möbius function (A008683).
MATHEMATICA
Table[Sum[(1 - MoebiusMu[2 n - k]^2), {k, n}], {n, 80}]
PROG
(PARI) a(n) = sum(i=1, n, 1 - moebius(2*n-i)^2); \\ Michel Marcus, Feb 11 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Oct 25 2017
STATUS
approved