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

Author

Eric M. Schmidt, Feb 09 2014

Keywords

• nonn
• base

Examples

			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.
		

Links

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

Crossrefs

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

Programs

PARI

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

Sage

# See A003226.