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 A266094 a(n) is the sum of the divisors of the smallest number k such that the symmetric representation of sigma(k) has n parts. 2
 1, 4, 13, 32, 104, 228, 576, 1408, 4104, 9824, 19152, 39816, 82944, 196992, 441294, 881280, 1911168, 4539024 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For more information see A239663 and A239665. LINKS FORMULA a(n) = A000203(A239663(n)). EXAMPLE Illustration of the symmetric representation of sigma(9): . .     _ _ _ _ _ 5 .    |_ _ _ _ _| .              |_ _ 3 .              |_  | .                |_|_ _ 5 .                    | | .                    | | .                    | | .                    | | .                    |_| . For n = 3 we have that 9 is the smallest number whose symmetric representation of sigma has three parts: [5, 3, 5], so a(3) = 5 + 3 + 5 = 13, equaling the sum of divisors of 9: sigma(9) = 1 + 3 + 9 = 13. For n = 7 we have that 357 is the smallest number whose symmetric representation of sigma has seven parts: [179, 61, 29, 38, 29, 61, 179], so a(7) = 179 + 61 + 29 + 38 + 29 + 61 + 179 = 576, equaling the sum of divisors of 357: sigma(357) = 1 + 3 + 7 + 17 + 21 + 51 + 119 + 357 = 576. CROSSREFS Cf. A000203, A196020, A235791, A236104, A237048, A237270, A237271, A237591, A237593, A239931-A239934, A239663, A239665, A240062, A245092, A262626. Sequence in context: A208638 A173277 A036420 * A054039 A302082 A124669 Adjacent sequences:  A266091 A266092 A266093 * A266095 A266096 A266097 KEYWORD nonn,hard,more AUTHOR Omar E. Pol, Dec 21 2015 EXTENSIONS a(14)-a(18) from Omar E. Pol, Jul 21 2018 STATUS approved

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Last modified April 9 06:59 EDT 2020. Contains 333344 sequences. (Running on oeis4.)