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A360121
Dirichlet convolution of A342001 with A342002.
3
0, 1, 1, 3, 1, 11, 1, 7, 7, 15, 1, 26, 1, 17, 20, 19, 1, 66, 1, 48, 22, 55, 1, 56, 9, 25, 44, 52, 1, 160, 1, 47, 60, 67, 26, 133, 1, 33, 30, 112, 1, 186, 1, 140, 135, 79, 1, 128, 9, 86, 72, 80, 1, 256, 64, 130, 38, 91, 1, 372, 1, 43, 155, 85, 34, 406, 1, 168, 84, 262, 1, 241, 1, 99, 127, 156, 66, 472, 1, 336, 130
OFFSET
1,4
FORMULA
a(n) = Sum_{d|n} A342001(n/d) * A342002(d).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A003557(n) = (n/factorback(factorint(n)[, 1]));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A342001(n) = (A003415(n) / A003557(n));
A360121(n) = sumdiv(n, d, A342001(n/d)*A342002(d));
CROSSREFS
Cf. A003415, A342001, A342002, A360122 (parity of terms).
Cf. also A347389, A359425.
Sequence in context: A119632 A201131 A277790 * A339175 A134761 A166752
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 19 2023
STATUS
approved