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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A225455 10-adic integer x such that x^9 == (10^n-1)/9 mod 10^n for all n. 2
1, 9, 3, 4, 8, 5, 1, 1, 9, 3, 5, 8, 6, 8, 7, 0, 8, 3, 8, 4, 5, 2, 6, 8, 7, 2, 8, 2, 5, 8, 9, 8, 2, 0, 5, 0, 8, 7, 4, 3, 6, 6, 9, 4, 4, 3, 6, 2, 2, 8, 0, 2, 2, 3, 7, 5, 2, 0, 5, 5, 6, 9, 2, 8, 2, 7, 1, 7, 1, 0, 8, 0, 6, 3, 0, 8, 8, 8, 6, 7, 6, 7, 5, 7, 4, 9, 8, 1, 5, 5, 2, 1, 7, 0, 3, 1, 6, 0, 6, 9 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
EXAMPLE
1^9 == 1 (mod 10).
91^9 == 11 (mod 100).
391^9 == 111 (mod 1000).
4391^9 == 1111 (mod 10000).
84391^9 == 11111 (mod 100000).
584391^9 == 111111 (mod 1000000).
MAPLE
A[1]:= 1: P:= 1:
for d from 2 to 100 do
R:= (expand((10^(d-1)*x+P)^9 - ((10^d-1)/9)) mod 10^d)/10^(d-1);
A[d]:= subs(msolve(R, 10), x);
P:= subs(10^(d-1)*A[d]+P);
od:
seq(A[i], i=1..100); # Robert Israel, Oct 03 2018
PROG
(PARI) n=0; for(i=1, 100, m=(10^i-1)/9; for(x=0, 9, if(((n+(x*10^(i-1)))^9)%(10^i)==m, n=n+(x*10^(i-1)); print1(x", "); break)))
CROSSREFS
Sequence in context: A021111 A242302 A102754 * A154184 A169791 A275519
KEYWORD
nonn,base
AUTHOR
Aswini Vaidyanathan, May 11 2013
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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 07:27 EDT 2024. Contains 371265 sequences. (Running on oeis4.)