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 A048348 a(n)^2 is the smallest square containing exactly n 3's. 2

%I

%S 6,56,586,1156,11547,57735,559769,1197219,6582806,36514844,350903624,

%T 1798230611,1825769244,48304278624,11547014044,577333277556,

%U 1527394295306,6582576498844,57465931849517

%N a(n)^2 is the smallest square containing exactly n 3's.

%C a(20) > 10^14. - _Giovanni Resta_, Jul 27 2018

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>

%t a[n_] := Block[{k=1}, While[DigitCount[k^2, 10, 3] != n, k++]; k]; Array[a, 6] (* _Giovanni Resta_, Jul 27 2018 *)

%Y Cf. A036510, A034982.

%K nonn,base,more

%O 1,1

%A _Patrick De Geest_, Mar 15 1999

%E More terms from _Jon E. Schoenfield_, Jan 11 2009

%E a(18)-a(19) from _Giovanni Resta_, Jul 27 2018

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Last modified January 27 15:24 EST 2021. Contains 340467 sequences. (Running on oeis4.)