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A349342
Sum of A026741 and its Dirichlet inverse.
2
2, 0, 0, 1, 0, 6, 0, 3, 9, 10, 0, 9, 0, 14, 30, 7, 0, 9, 0, 15, 42, 22, 0, 15, 25, 26, 27, 21, 0, 0, 0, 15, 66, 34, 70, 18, 0, 38, 78, 25, 0, 0, 0, 33, 45, 46, 0, 27, 49, 25, 102, 39, 0, 27, 110, 35, 114, 58, 0, 15, 0, 62, 63, 31, 130, 0, 0, 51, 138, 0, 0, 36, 0, 74, 75, 57, 154, 0, 0, 45, 81, 82, 0, 21, 170, 86
OFFSET
1,1
LINKS
FORMULA
a(n) = A026741(n) + A349341(n).
a(1) = 2, and for n > 1, a(n) = -Sum_{d|n, 1<d<n} A026741(d) * A349341(n/d).
PROG
(PARI)
A026741(n) = if(n%2, n, n/2);
A349341(n) = { my(f = factor(n)); prod(i=1, #f~, if(2==f[i, 1], -1, if(1==f[i, 2], -f[i, 1], 0))); };
A349342(n) = (A026741(n)+A349341(n));
CROSSREFS
Sequence in context: A158785 A346243 A349916 * A365712 A349914 A354105
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 15 2021
STATUS
approved