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A300718 Möbius transform of A010848, number of numbers k <= n such that at least one prime factor of n is not a prime factor of k. 3
0, 1, 2, 1, 4, 2, 6, 2, 4, 4, 10, 4, 12, 6, 8, 4, 16, 6, 18, 8, 12, 10, 22, 8, 16, 12, 12, 12, 28, 8, 30, 8, 20, 16, 24, 10, 36, 18, 24, 16, 40, 12, 42, 20, 24, 22, 46, 16, 36, 20, 32, 24, 52, 18, 40, 24, 36, 28, 58, 16, 60, 30, 36, 16, 48, 20, 66, 32, 44, 24, 70, 20, 72, 36, 40, 36, 60, 24, 78, 32, 36, 40, 82, 24, 64, 42, 56, 40, 88, 24, 72 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
a(n) = Sum_{d|n} A008683(n/d)*A010848(d).
a(n) = A000010(n) - A300717(n).
a(n) = A010848(n) - A300720(n).
PROG
(PARI)
A003557(n) = { my(f=factor(n)); for (i=1, #f~, f[i, 2] = max(0, f[i, 2]-1)); factorback(f); }; \\ From A003557
A010848(n) = (n - A003557(n));
A300718(n) = sumdiv(n, d, moebius(n/d)*A010848(d));
CROSSREFS
Sequence in context: A175542 A076686 A114810 * A093819 A089929 A131888
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 11 2018
STATUS
approved

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Last modified May 31 22:12 EDT 2024. Contains 373007 sequences. (Running on oeis4.)