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 A141414 Least k for which A140361(n) = k. 6
 1, 3, 5, 7, 13, 41, 113, 311, 1821, 10267, 74587, 1015453, 12550793 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS EXAMPLE a(1) = 3: 3 can be written as 2+1, requiring 1 operation a(2) = 5: 5 = (2+1)+2, the lowest number requiring 2 operations a(3) = 7: ((2+2)+1)+2, the lowest number requiring 3 operations a(4) = 13: (2+1)*3+2+2 (Note: 3 = 2+1 reused) a(5) = 41: (2+1)*2*6+3+2 (3 = 2+1 reused, 6 = 3*2 reused) a(6) = 113: ((2+1)*3+3+1)*9-4 a(7) = 311: ((2+1)*3*3+1)*(9+2)+3 a(8) = 1821: (2+(2+1))*(3+(2+2)*4)*19+16 a(9) = 10267: (1+(2+(2+1))*(3*3))*(5*45-2)+9 a(10) = 74587: (2+1)*(((2*(3*3)*9-2)-3)*157+160)+160 CROSSREFS Cf. A217032. Sequence in context: A244452 A057187 A163080 * A236464 A064268 A235873 Adjacent sequences:  A141411 A141412 A141413 * A141415 A141416 A141417 KEYWORD hard,more,nonn AUTHOR Leonid Broukhis, Aug 04 2008 EXTENSIONS Comment removed and three new entries added by Jeffrey Wang (jeffreyw(AT)stanford.edu), Oct 10 2009 a(11)-a(12) from Gil Dogon, Apr 25 2013 STATUS approved

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Last modified September 19 15:37 EDT 2021. Contains 347564 sequences. (Running on oeis4.)