A237583 Automorphic numbers: n^2 ends with n in base 6.

0, 1, 3, 4, 9, 28, 81, 136, 1216, 6561, 16768, 29889, 76545, 203392, 636417, 1043200, 3995649, 6082048, 24151041, 36315136, 326481921, 689278977, 1487503360, 11573190657, 76876660737, 155240824833, 314944159744, 785129144320, 2035980763137, 4857090670593

Offset

1,3

Links

Eric M. Schmidt, Table of n, a(n) for n = 1..1000

Example

From A201821:
a(3) = (3)_6 = 3 since 3^2 = 9 = (13)_6 ends with 3 in base 6.
a(4) = (4)_6 = 4 since 4^2 = 16 = (24)_6 ends with 4 in base 6.
a(5) = (13)_6 = 9 since 9^2 = 81 = (213)_6 ends with 13 in base 6.

Prog

(Sage) # See A003226.
(PARI) isok(n) = ((n^2-n) % 6^(#digits(n, 6))) == 0; \\ Michel Marcus, Mar 08 2014

Crossrefs

Cf. A201821 (written in base 6), A003226, A201918, A201919, A201921, A201948.

Sequence in context: A247087 A270756 A105229 * A362353 A080849 A058857

Adjacent sequences: A237580 A237581 A237582 * A237584 A237585 A237586

Keyword

nonn,base

Author

Eric M. Schmidt, Feb 09 2014

Status

approved