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 A335883 The least k for which A335884(k) = n. 1
 1, 3, 5, 11, 23, 47, 109, 229, 457, 1033, 2161, 4703, 10079, 20663, 43223, 94033, 208849, 420457, 872687, 1849921, 3699841, 8748001, 17496001, 36998411 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Because A335884 is fully additive and a(1) = 3, we have a(n) <= 3^n and in particular, a(n+1) <= 3*a(n), n > 0 and more generally a(n + m) <= a(n) * a(m) where m, n >= 0. (See also comments in A334099.) a(16) = 208849 = 457^2 = a(8)*a(8) is the first composite term. LINKS FORMULA For all n >= 0, A335884(a(n)) = n. CROSSREFS Cf. A335884. Sequence in context: A072828 A290114 A032803 * A030494 A246491 A084361 Adjacent sequences:  A335880 A335881 A335882 * A335884 A335885 A335886 KEYWORD nonn,more AUTHOR Antti Karttunen, Jun 29 2020 EXTENSIONS a(21)-a(23) from Jinyuan Wang, Jul 08 2020 STATUS approved

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Last modified September 16 18:26 EDT 2021. Contains 347473 sequences. (Running on oeis4.)