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 A324830 Number of divisors d of n such that A323243(d) is a multiple of 3. 6
 1, 1, 2, 1, 1, 3, 2, 1, 3, 1, 1, 4, 2, 3, 3, 2, 1, 4, 2, 1, 4, 2, 1, 5, 1, 3, 4, 4, 2, 4, 1, 2, 3, 1, 3, 5, 2, 3, 4, 1, 1, 6, 2, 2, 5, 1, 1, 7, 3, 1, 3, 4, 2, 6, 1, 5, 4, 3, 1, 5, 2, 2, 6, 2, 3, 6, 1, 1, 3, 5, 2, 7, 1, 3, 4, 4, 3, 6, 2, 2, 5, 1, 1, 8, 2, 3, 4, 3, 2, 7, 4, 1, 3, 2, 3, 8, 1, 5, 5, 2, 2, 5, 1, 5, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552) FORMULA a(n) = A000005(n) - (A324831(n) + A324832(n)). For all n >= 1, a(A000040(n)) = 2-A000035(n). PROG (PARI) A324830(n) = sumdiv(n, d, (0==(A323243(d))%3)); CROSSREFS Cf. A000005, A156552, A323243, A324831, A324832. Sequence in context: A152538 A329359 A235682 * A141110 A325758 A280073 Adjacent sequences:  A324827 A324828 A324829 * A324831 A324832 A324833 KEYWORD nonn AUTHOR Antti Karttunen, Mar 16 2019 STATUS approved

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Last modified December 15 17:03 EST 2019. Contains 330000 sequences. (Running on oeis4.)