A137028 Numbers k such that k and k^2 use only the digits 1, 3, 4, 7 and 8.

1, 38, 88, 1188, 4141, 8878, 11478, 18471, 33878, 183878, 844878, 887771, 1347141, 3381378, 33883878, 43344878, 88811471, 177317438, 178374141, 333374141, 338841141, 344743878, 844877141, 887377438, 3334348188, 3441183188, 8817473471, 11483831378, 13347183878, 13371137378, 13484747378, 17713783188, 17744811471

Offset: 1

Author

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

Keywords

• base
• nonn

Comments

Generated with DrScheme.

Examples

			344787487347378^2 = 118878411431318344438843474884.
		

Links

• Jonathan Wellons, Table of n, a(n) for n = 1..112
• J. Wellons, Tables of Shared Digits [archived]

Programs

Mathematica

Module[{c={1,3,4,7,8}},Table[Select[FromDigits/@Tuples[c,n],SubsetQ[c,IntegerDigits[#^2]]&],{n,11}]]//Flatten (* Harvey P. Dale, Feb 22 2024 *)