The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A243913 Decimal expansion of 9^(9^(9^9)) = 9^^4. 10
 2, 1, 4, 1, 9, 8, 3, 2, 9, 4, 7, 9, 6, 8, 0, 5, 6, 1, 1, 3, 3, 3, 3, 6, 4, 3, 7, 3, 4, 4, 2, 4, 8, 0, 8, 3, 0, 1, 4, 7, 2, 2, 7, 0, 7, 2, 8, 4, 5, 1, 2, 8, 4, 8, 8, 7, 0, 6, 5, 1, 6, 1, 9, 5, 9, 8, 2, 8, 0, 8, 7, 4, 9, 6, 5, 6, 7, 0, 4, 8, 4, 7, 0, 3, 6, 1, 1, 8, 4, 4, 7, 2, 4, 9, 9, 1, 7, 3, 6, 8, 5, 3, 4, 8, 8 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The offset is 1 because the true offset would be 10^(4.085349171835445 * 10^369693099), which is too large to be written out in full in the OEIS or, for that matter, the Universe. 9^8^7^6^5^4^3^2^1^0 (mod 100000000) = 79806721; 9^8^7^6^5^4^3^2^1^0 = 10^10^10^10^(4.829261035877073 * 10^183230). REFERENCES Ilan Vardi, "Computational Recreations in Mathematica," Addison-Wesley Publishing Co., Redwood City, CA, 1991, pages 226-229. LINKS Hans Havermann and Robert G. Wilson v, Table of n, a(n) for n = 1..10000 Robert P. Munafo, Hyper4 Iterated Exponential Function Robert P. Munafo and Robert G. Wilson v, Mathematica coding for "SuperPowerMod" from Vardi Robert G. Wilson v, Mathematica coding for "SuperPowerMod" from Vardi FORMULA 9^(9^(9^9)) = ((((( ... 387420478 ... (((((9^9)^9)^9)^9)^9) ... 387420478 ... ^9)^9)^9)^9)^9)^9. EXAMPLE =2141983294796805611333364373442480830147227072845128488706516195982808749656704847036118447249917368...(4.085349171835445... * 10^369693099) ... 3771540670946945552331518959254852001991324340257630363975097419408973491530163140828233401045865289. The first and last 100 digits are shown above, with the intervening digits omitted. The final one hundred digits cannot be computed with: PowerMod[9, 9^9^9, 10^100] with any version of Mathematica before version 9. Instead (* Import Mmca coding for "SuperPowerMod" and "LogStar" from text file and then *) SuperPowerMod[9, 4, 10^100]. MATHEMATICA nbrdgt = 105; f[base_, exp_] := RealDigits[ 10^FractionalPart[ N[ exp*Log10[ base], nbrdgt + Floor[ Log10[ exp]] + 2]], 10, nbrdgt][[1]]; f[ 9, 9^9^9] (* needs version 9.0 to run *) CROSSREFS Cf. A002488, A054382, A085667, A202955, A054382, A014221, A241291, A241292, A241293, A241294, A241295, A241296, A241297, A241298, A241299. Sequence in context: A146418 A146011 A104620 * A186724 A145930 A145762 Adjacent sequences: A243910 A243911 A243912 * A243914 A243915 A243916 KEYWORD nonn,cons,fini,hard AUTHOR Hans Havermann and Robert G. Wilson v, Jun 14 2014 EXTENSIONS Keyword: fini added by Jianing Song, Sep 18 2019 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 29 03:36 EDT 2023. Contains 365749 sequences. (Running on oeis4.)