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 A294890 Number of divisors of n that are primitively abundant (A091191). 4
 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 3, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,36 COMMENTS Records occur at 1, 12, 36, 60, 180, 420, 840, 2520, 7560, 9240, 24024, 60060, ... and they are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, ... Ten occurs for the first time as a(40040) = 10. LINKS Antti Karttunen, Table of n, a(n) for n = 1..70560 FORMULA a(n) = Sum_{d|n} A294930(d). EXAMPLE Divisors of 24 are 1, 2, 3, 4, 6, 8, 12, 24. Only 12 is in A091191, thus a(24) = 1. Divisors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, 36. Of these 12 and 18 are found in A091191, thus a(36) = 2. PROG (PARI) A294937(n) = (sigma(n)>(2*n)); A294929(n) = sumdiv(n, d, (d

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Last modified April 18 12:34 EDT 2019. Contains 322209 sequences. (Running on oeis4.)