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%I #10 Jul 02 2018 01:42:27
%S 0,1,4,9,79,799,9999,499999,19999999,999999999,199999999999,
%T 49999999999999,9999999999999999,7999999999999999999,
%U 7999999999999999999999,9999999999999999999999999
%N Smallest number whose digit sum is n^2.
%H Harry J. Smith, <a href="/A061104/b061104.txt">Table of n, a(n) for n = 0..94</a>
%F a(n) = ((n^2 mod 9) + 1)*10^floor(n^2/9) - 1. - _Henry Bottomley_, Apr 24 2001
%e a(5) = 799, 7 + 9 + 9 = 25 = 5^2.
%o (PARI) { for (n=0, 94, a=(n^2%9 + 1)*10^(n^2\9) - 1; write("b061104.txt", n, " ", a) ) } \\ _Harry J. Smith_, Jul 18 2009
%Y Cf. A051885, A061105.
%K nonn,base
%O 0,3
%A _Amarnath Murthy_, Apr 20 2001
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