A229522 -id:A229522 - cp's OEIS frontend

A120962 Final digit (in decimal system) of n^(n^n), i.e., n^(n^n) mod 10.

0, 1, 6, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 6, 9, 0, 1, 6, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 6, 9, 0, 1, 6, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 6, 9, 0, 1, 6, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 6, 9, 0, 1, 6, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 6, 9, 0, 1, 6, 7, 6, 5

Offset: 0

N. J. A. Sloane, Jul 19 2006, Oct 26 2007

Periodic sequence with period length 20. - Arkadiusz Wesolowski, Feb 12 2012

Index entries for linear recurrences with constant coefficients, signature (0,1,0,-1,0,1,0,-1,0,1,0,-1,0,1,0,-1,0,1).

Cf. A061505, A229522, A229784.

Maple
```
seq(n &^ (n^n) mod 10, n=0..105);
```

Join[{0}, Table[PowerMod[n, n^n, 10], {n, 100}]] (* Stefan Steinerberger, Nov 23 2007 *)

a(n)=if(n%10,lift(Mod(n,10)^lift(Mod(n,20)^n)),0) \\ Charles R Greathouse IV, Feb 12 2012

def A120962(n): return pow(n,n**n,10) # Chai Wah Wu, Sep 22 2023

a(n) = A010879(A002488(n)). - Michel Marcus, Aug 04 2015

More terms from Stefan Steinerberger, Nov 23 2007

A364789 Initial digit of (n^n)^n (A002489(n)).

Original entry on oeis.org

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

Offset: 0

Marco Ripà, Aug 08 2023

a(0) = 1 is from (0^0)^0 = 1 per A002489.

The author conjectures that this sequence obeys the well-known Benford's law.

			a(4) = 4, since (4^4)^4 = 4^(4^2) = 4294967296.

Paolo Xausa, Table of n, a(n) for n = 0..1000
Pointless Large numbers stuff by Cookiefonster, 2.03 The Weak Hyper-Operators.
Wikipedia, Benford's law.

Cf. A000030, A002489, A241299, A363746, A364837, A364855.

Cf. A229522 (final digit).

A364789[n_] := If[n == 0, 1, First[IntegerDigits[(n^n)^n]]];
Array[A364789, 100, 0] (* Paolo Xausa, Jan 31 2024 *)

def A364789(n): return int(str((n**n)**n)[0]) # Chai Wah Wu, Aug 10 2023

a(n) = floor(((n^n)^n)/10^floor(log_10((n^n)^n))).

a(n) = A000030(A002489(n)).

cp's OEIS Frontend

A120962 Final digit (in decimal system) of n^(n^n), i.e., n^(n^n) mod 10.

Views

Author

Keywords

Comments

Links

Crossrefs

Programs

Maple

Mathematica

PARI

Python

Formula

Extensions