A030993 8-automorphic numbers: final digits of 8*n^2 agree with n.

2, 72, 672, 8672, 88672, 388672, 3388672, 23388672, 223388672, 223388672, 10223388672, 510223388672, 7510223388672, 67510223388672, 967510223388672, 7967510223388672, 67967510223388672

Offset

1,1

Comments

a(n) is the unique positive integer less than 10^n such that a(n) is divisible by 2^n and 8*a(n) - 1 is divisible by 5^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

Prog

(Sage) [crt(0, inverse_mod(8, 5^n), 2^n, 5^n) for n in range(1, 1001)] # Eric M. Schmidt, Aug 18 2012

Crossrefs

Sequence in context: A272757 A187707 A163274 * A283568 A070775 A157061

Adjacent sequences: A030990 A030991 A030992 * A030994 A030995 A030996

Keyword

nonn,base

Author

Eric W. Weisstein

Status

approved