A136959 Numbers k such that k and k^2 use only the digits 0, 4, 7, 8 and 9.

0, 7, 70, 88, 97, 700, 707, 878, 880, 948, 970, 997, 7000, 7007, 7070, 8780, 8798, 8800, 8947, 9480, 9700, 9898, 9970, 9997, 70000, 70007, 70070, 70700, 70707, 87798, 87800, 87980, 88000, 89448, 89470, 94800, 97000, 98980, 99448, 99700, 99970, 99997, 700000, 700007, 700070, 700700, 707000, 707070, 877898, 877980, 877998, 878000, 879800

Offset

1,2

Comments

Generated with DrScheme.

Links

Jonathan Wellons, Table of n, a(n) for n = 1..1058

J. Wellons, Tables of Shared Digits [archived]

Example

8989409879898^2 = 80809489988807774784490404.

Mathematica

With[{c={0, 4, 7, 8, 9}}, Select[FromDigits/@Tuples[c, 6], SubsetQ[ c, IntegerDigits[ #^2]]&]] (* Harvey P. Dale, Jun 02 2019 *)

Crossrefs

Sequence in context: A062901 A204094 A061476 * A136952 A136960 A003363

Adjacent sequences: A136956 A136957 A136958 * A136960 A136961 A136962

Keyword

base,nonn

Author

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

Status

approved