A030986 3-automorphic numbers ending in 5: final digits of 3*n^2 agree with n.

5, 75, 875, 6875, 96875, 296875, 4296875, 4296875, 404296875, 9404296875, 39404296875, 639404296875, 6639404296875, 86639404296875, 86639404296875, 2086639404296875, 52086639404296875

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn
• base

Comments

a(n) is the unique positive integer less than 10^n such that a(n) is divisible by 5^n and 3*a(n) - 1 is divisible by 2^n. - Eric M. Schmidt, Aug 18 2012

Links

• Eric M. Schmidt, Table of n, a(n) for n = 1..1000
• Index entries for sequences related to automorphic numbers
• Index entries for sequences related to final digits of numbers
• Eric Weisstein's World of Mathematics, Automorphic Number

Programs

Sage

[crt(inverse_mod(3, 2^n), 0, 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012