A136831 Numbers k such that k and k^2 use only the digits 0, 1, 2 and 7.

0, 1, 10, 11, 100, 101, 110, 1000, 1001, 1010, 1011, 1100, 1101, 10000, 10001, 10010, 10011, 10100, 10110, 11000, 11001, 11010, 100000, 100001, 100010, 100011, 100100, 100101, 100110, 101000, 101001, 101100, 110000, 110001, 110010, 110100, 1000000, 1000001, 1000010, 1000011, 1000100, 1000101, 1000110, 1001000, 1001010, 1001100, 1010000

Offset

1,3

Comments

Generated with DrScheme.

Links

Jonathan Wellons, Table of n, a(n) for n = 1..1361

J. Wellons, Tables of Shared Digits [archived]

Example

110100010001011^2 = 12122012202222722220221022121.

Mathematica

With[{c={0, 1, 2, 7}}, Select[FromDigits/@Tuples[c, 7], SubsetQ[ c, IntegerDigits[ #^2]]&]] (* Harvey P. Dale, Dec 21 2014 *)

Crossrefs

Sequence in context: A136808 A136836 A136827 * A204009 A371047 A043681

Adjacent sequences: A136828 A136829 A136830 * A136832 A136833 A136834

Keyword

base,nonn,changed

Author

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

Status

approved