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A366417
a(n) = A006571(A005117(n)).
0
1, -2, -1, 1, 2, -2, -2, 1, 4, 4, -1, -2, 0, 2, -2, -1, -8, 0, 2, 7, -1, 4, -2, 3, 0, -4, -8, -4, -6, 2, 8, 2, -6, 1, 0, 0, 5, 12, -14, 4, 2, -7, 1, 4, -3, 4, -6, -2, 8, -10, 16, -6, -2, 12, 0, 15, -8, -7, -16, 0, -7, 2, -4, -16, 2, 12, 18, 10, -2, -3, 9, 0, -1
OFFSET
1,2
FORMULA
a(n) = A006571(A005117(n)).
Conjecture: a(n) = A366450(A005117(n)), verified up to n = 98.
MATHEMATICA
nn = 73; squareFree = Select[Range[8*nn], SquareFreeQ]; b[n_] := SeriesCoefficient[q (Product[(1 - q^k), {k, 11, n, 11}] Product[1 - q^k, {k, n}])^2, {q, 0, n}]; Table[b[squareFree[[n]]], {n, 1, nn}]
KEYWORD
sign
AUTHOR
Mats Granvik, Oct 10 2023
STATUS
approved