|
|
A030991
|
|
7-automorphic numbers ending in 5: final digits of 7n^2 agree with n.
|
|
1
|
|
|
5, 75, 375, 4375, 84375, 984375, 8984375, 58984375, 458984375, 5458984375, 45458984375, 845458984375, 2845458984375, 22845458984375, 322845458984375, 2322845458984375, 22322845458984375
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
a(n) is the unique positive integer less than 10^n such that a(n) is divisible by 5^n and 7a(n) - 1 is divisible by 2^n. - Eric M. Schmidt, Aug 18 2012
|
|
LINKS
|
|
|
PROG
|
(Sage) [crt(inverse_mod(7, 2^n), 0, 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|