A053881 Squares composed of digits {1,2,4}.
1, 4, 121, 144, 441, 1444, 114244, 2214144, 11142244, 121242121, 421111441, 1111422244, 44424414441, 111114222244, 11111142222244, 214222214414224, 242441124211441, 411244411422244, 1111111422222244, 2111211444222241
Offset: 1
Examples
Terms include 1444, 114244, 11142244, 1111422244, 111114222244, 11111142222244, etc. - _Andrew Howroyd_, Sep 28 2024
Links
- Zhao Hui Du, Table of n, a(n) for n = 1..54
- Patrick De Geest, Squares containing at most three distinct digits, Index entries for related sequences
Crossrefs
Cf. A053880.
Formula
a(n) = A053880(n)^2.
Comments