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A091409 a(n) = smallest m such that A090822(m) = n. 1
1, 3, 9, 220 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..4.

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].

Index entries for sequences related to Gijswijt's sequence

FORMULA

a(n) is about 2^(2^(3^(4^(5^...^(n-1))))).

CROSSREFS

Sequence in context: A062228 A196864 A279834 * A027891 A073889 A211898

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 December 9 17:18 EST 2019. Contains 329879 sequences. (Running on oeis4.)