A136860 Numbers k such that k and k^2 use only the digits 0, 1, 4, 6 and 7.

0, 1, 4, 10, 40, 100, 400, 1000, 1071, 4000, 7776, 10000, 10710, 10771, 40000, 77760, 100000, 106771, 106776, 107100, 107710, 400000, 777600, 1000000, 1007046, 1067710, 1067760, 1071000, 1077100, 1077776, 4000000, 6406771, 7771774, 7776000, 10000000, 10070460, 10677100, 10677600, 10710000, 10771000, 10777760, 40000000, 64067710

Offset

1,3

Comments

Generated with DrScheme.

Links

Jonathan Wellons, Table of n, a(n) for n = 1..316

Jonathan Wellons, Tables of Shared Digits

Example

646076401416771^2 = 417414716467644616616040066441.

Mathematica

With[{c={0, 1, 4, 6, 7}}, Select[FromDigits/@Tuples[c, 8], SubsetQ[ c, IntegerDigits[ #^2]]&]] (* Harvey P. Dale, Jul 16 2020 *)

Crossrefs

Cf. A000290.

Sequence in context: A238721 A077811 A136855 * A136859 A051479 A149204

Adjacent sequences: A136857 A136858 A136859 * A136861 A136862 A136863

Keyword

base,nonn

Author

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

Status

approved