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 A058838 a(n) = 1 + sum of the anti-divisors of n. 6
 1, 1, 3, 4, 6, 5, 11, 9, 9, 15, 13, 14, 20, 17, 19, 15, 29, 29, 19, 25, 23, 37, 35, 24, 40, 25, 43, 47, 25, 37, 43, 59, 49, 31, 53, 33, 51, 71, 53, 56, 42, 67, 57, 41, 87, 59, 61, 57, 73, 81, 43, 95, 89, 53, 75, 57, 75, 97, 91, 108, 58, 79, 113, 47, 85 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS See A066272 for definition of anti-divisor. LINKS Jon Perry, Anti-divisors [Broken link] Jon Perry, The Anti-divisor [Cached copy] Jon Perry, The Anti-divisor: Even More Anti-Divisors [Cached copy] FORMULA a(n) = A066417(n) + 1. EXAMPLE Consider n = 18: 2n-1, 2n, 2n+1 are 35, 36, 37 with odd divisors > 1 {5,7,35}, {3,9}, {37} respectively and quotients {7, 5, 1}, {12, 4}, {1}; so the anti-divisors of 18 are 4, 5, 7, 12. Therefore a(18) = 1 + 28 = 29. CROSSREFS Cf. A066417, A066241, A066452. Sequence in context: A083342 A016655 A057757 * A001177 A053991 A276814 Adjacent sequences:  A058835 A058836 A058837 * A058839 A058840 A058841 KEYWORD nonn AUTHOR Jon Perry, Dec 28 2001 STATUS approved

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Last modified October 17 07:05 EDT 2018. Contains 316276 sequences. (Running on oeis4.)