A129810 9^(9^9) mod n.

0, 1, 0, 1, 4, 3, 1, 1, 0, 9, 5, 9, 1, 1, 9, 9, 9, 9, 1, 9, 15, 5, 8, 9, 14, 1, 0, 1, 9, 9, 4, 9, 27, 9, 29, 9, 1, 1, 27, 9, 9, 15, 11, 5, 9, 31, 34, 9, 15, 39, 9, 1, 9, 27, 49, 1, 39, 9, 28, 9, 34, 35, 36, 9, 14, 27, 22, 9, 54, 29, 12, 9, 72, 1, 39, 1, 71, 27, 21, 9, 0, 9, 61, 57, 9, 11, 9, 49, 42

Offset

1,5

Comments

Eventually constant: a(n) = 9^9^9 for all n > 9^9^9 ~ 4.28*10^369693099. - M. F. Hasler, Feb 24 2018

Links

Table of n, a(n) for n=1..89.

Math Forum, Dr. Math 9^387420489, [09/10/1997]

Math Forum, Dr. Math Digits of 9^9^9, 06/11/2003

Index entries for eventually constant sequences.

Formula

a(n) = 0 for all n = 3^k, 0 <= k <= 2*9^9; a(n) = 9^9^9 for all n > 9^9^9. - M. F. Hasler, Feb 24 2018

Example

[9^(9^9)] mod 1 =0
[9^(9^9)] mod 2 =1
[9^(9^9)] mod 9 =0
[9^(9^9)] mod (3*387420489) =0

Mathematica

Table[PowerMod[9, 9^9, n], {n, 1, 100}]

Prog

(PARI) a(n)=lift(Mod(9, n)^9^9) \\ Charles R Greathouse IV, Jul 02 2012

Crossrefs

Cf. A081230, A214128 (6^6^6 mod n).

Sequence in context: A355401 A195596 A332054 * A016500 A211451 A371809

Adjacent sequences: A129807 A129808 A129809 * A129811 A129812 A129813

Keyword

nonn,easy

Author

Marvin Ray Burns, May 19 2007

Status

approved