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There are infinitely many nonzero squares in this sequence; for example a(10^(4n)-10^(2n)) = [10^n*(10^(2n)-1)]^2. - David Wasserman, Dec 07 2004
Table of n, a(n) for n=1..46.
a(n) = n*(10^d -1-n), where d is the number of digits in n.
a(n) = n*A061601(n). - David Wasserman, Dec 07 2004
Sequence in context: A235143 A179186 A192045 * A114456 A138666 A072835
Adjacent sequences: A084018 A084019 A084020 * A084022 A084023 A084024
Amarnath Murthy, May 23 2003
More terms from David Wasserman, Dec 07 2004