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A331376
Dirichlet convolution of the reduced totient function with itself.
0
1, 2, 4, 5, 8, 8, 12, 8, 16, 16, 20, 16, 24, 24, 24, 16, 32, 32, 36, 32, 36, 40, 44, 24, 56, 48, 60, 48, 56, 48, 60, 32, 60, 64, 72, 60, 72, 72, 72, 48, 80, 72, 84, 80, 88, 88, 92, 44, 120, 112, 96, 96, 104, 120, 120
OFFSET
1,2
COMMENTS
Differs from A029935 when A002322 differs from A000010.
FORMULA
a(n) = Sum{d|n} A002322(d) * A002322(n/d).
PROG
(PARI) a(n) = sumdiv(n, d, lcm(znstar(d)[2]) * lcm(znstar(n/d)[2]));
CROSSREFS
KEYWORD
nonn
AUTHOR
Torlach Rush, Jan 14 2020
STATUS
approved