login
A053881
Squares composed of digits {1,2,4}.
3
1, 4, 121, 144, 441, 1444, 114244, 2214144, 11142244, 121242121, 421111441, 1111422244, 44424414441, 111114222244, 11111142222244, 214222214414224, 242441124211441, 411244411422244, 1111111422222244, 2111211444222241
OFFSET
1,2
COMMENTS
Includes all numbers of the form ((10^k-1)/3 + 5)^2 for k > 1. - Andrew Howroyd, Sep 28 2024
FORMULA
a(n) = A053880(n)^2.
EXAMPLE
Terms include 1444, 114244, 11142244, 1111422244, 111114222244, 11111142222244, etc. - Andrew Howroyd, Sep 28 2024
CROSSREFS
Cf. A053880.
Sequence in context: A239187 A062081 A374723 * A075114 A017186 A355751
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Mar 15 2000
STATUS
approved