A241296 Decimal expansion of 7^(7^(7^7)) = 7^^4.

7, 8, 3, 3, 0, 0, 5, 2, 3, 7, 4, 8, 0, 0, 5, 5, 5, 6, 5, 4, 0, 3, 8, 5, 4, 0, 9, 4, 7, 5, 4, 6, 5, 3, 0, 8, 2, 9, 1, 9, 0, 4, 4, 3, 9, 8, 5, 5, 8, 7, 7, 0, 1, 3, 1, 4, 8, 2, 1, 1, 9, 7, 0, 3, 1, 8, 5, 0, 2, 8, 4, 3, 6, 3, 3, 9, 7, 2, 6, 3, 4, 4, 4, 4, 2, 9, 7, 2, 3, 3, 8, 2, 8, 9, 4, 1, 0, 0, 4, 5, 1, 7, 7, 8, 7

Offset

1,1

Comments

The offset is 1 because the true offset would be 3.177419493... * 10^695974, which is too large to be represented properly in the OEIS.

Links

Table of n, a(n) for n=1..105.

Robert P. Munafo, Hyper4 Iterated Exponential Function..

Formula

7^(7^(7^7)) = ((((( ... 823532 ... (((((7^7)^7)^7)^7)^7) ... 823532 ... ^7)^7)^7)^7)^7)^7.

Example

7833005237480055565403854094754653082919044398558770131482119703185028436339726344442972338289410045...(3.177419493... * 10^695974)...1766659134033863120639301828875443004447501140571853058472378511366058254036038182879357182733172343.
The above line shows the first one hundred decimal digits and the last one hundred digits with the number of unrepresented digits in parenthesis.
The final one hundred digits where computed by: PowerMod[7, 7^7^7, 10^100].

Mathematica

nbrdgt = 105; f[base_, exp_] := RealDigits[ 10^FractionalPart[ N[ exp*Log10[ base], nbrdgt + Floor[ Log10[ exp]] + 2]], 10, nbrdgt][[1]]; f[ 7, 7^7^7]

Crossrefs

Cf. A085667, A202955, A054382, A014221, A241291, A241292, A241293, A241294, A241295, A241297, A241298, A241299, A243913.

Sequence in context: A378129 A064207 A020843 * A083648 A133613 A379214

Adjacent sequences: A241293 A241294 A241295 * A241297 A241298 A241299

Keyword

nonn,cons,fini

Author

Robert Munafo and Robert G. Wilson v, Apr 18 2014

Extensions

Keyword: fini added by Jianing Song, Sep 18 2019

Status

approved