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A053903
Squares composed of digits {1,5,6}.
3
1, 16, 1156, 6561, 111556, 556516, 6661561, 11115556, 165611161, 1111155556, 1566655561, 6661661161, 111111555556, 1551155666116, 1561665111556, 11111115555556, 156166661115556, 1111111155555556, 111111111555555556, 5115511551651111556, 11111111115555555556
OFFSET
1,2
COMMENTS
Includes all numbers of the form ((10^k-1)/3 + 1)^2. - Andrew Howroyd, Oct 18 2024
FORMULA
a(n) = A053902(n)^2. - Andrew Howroyd, Oct 18 2024
CROSSREFS
Cf. A053902.
Sequence in context: A374493 A279295 A353029 * A254333 A102807 A373453
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Mar 15 2000
STATUS
approved