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 A091409 a(n) is the smallest m such that A090822(m) = n. 1
 1, 3, 9, 220 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS D. C. Gijswijt, Krulgetallen, Pythagoras, 55ste Jaargang, Nummer 3, Jan 2016. (Shows that the sequence is infinite) F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, A Slow-Growing Sequence Defined by an Unusual Recurrence, J. Integer Sequences, Vol. 10 (2007), #07.1.2. F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, A Slow-Growing Sequence Defined by an Unusual Recurrence [pdf, ps]. FORMULA a(n) is about 2^(2^(3^(4^(5^...^(n-1))))). CROSSREFS Sequence in context: A062228 A196864 A279834 * A027891 A073889 A332586 Adjacent sequences:  A091406 A091407 A091408 * A091410 A091411 A091412 KEYWORD nonn AUTHOR N. J. A. Sloane, based on a suggestion from Dion Gijswijt (gijswijt(AT)science.uva.nl), Mar 04 2004 EXTENSIONS Sequence is infinite but next term, about 10^(10^23.09987) (see A091787), is too large to include. STATUS approved

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Last modified June 12 08:13 EDT 2021. Contains 344943 sequences. (Running on oeis4.)