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 A193551 Smallest number with n as multiplicative projection. 3
 1, 2, 3, 4, 5, 6, 7, 16, 27, 10, 11, 12, 13, 14, 15, 256, 17, 24, 19, 20, 21, 22, 23, 36, 3125, 26, 19683, 28, 29, 30, 31, 65536, 33, 34, 35, 72, 37, 38, 39, 80, 41, 42, 43, 44, 135, 46, 47, 144, 823543, 160, 51, 52, 53, 216, 55, 112, 57, 58, 59, 60, 61, 62 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A000026(a(n)) = n and A000026(m) <> n for m < a(n); a(p^k) = p^(p^(k-1)), p prime, k > 0; the sequence is not multiplicative, but for coprime odd numbers u, v: a(u*v) = a(u) * a(v); A078779 gives fixed points: a(A078779(n)) = A078779(n). LINKS PROG (Haskell) import Data.List (elemIndex, findIndices) import Data.Maybe (fromJust) a193551 n = (fromJust \$ elemIndex n a000026_list) + 1 CROSSREFS Sequence in context: A132028 A332535 A285724 * A277439 A069188 A085158 Adjacent sequences:  A193548 A193549 A193550 * A193552 A193553 A193554 KEYWORD nonn AUTHOR Reinhard Zumkeller, Aug 27 2011 STATUS approved

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Last modified September 26 09:15 EDT 2021. Contains 347664 sequences. (Running on oeis4.)