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Numbers of the form 3^x-y^2 >= 0.
3

%I #14 May 14 2017 03:00:41

%S 0,1,2,3,5,8,9,11,17,18,23,26,27,32,45,47,53,56,65,71,72,74,77,80,81,

%T 83,99,104,122,143,153,161,162,179,194,200,207,218,227,234,239,242,

%U 243,245,251,288,320,329,338,362,368,405,423,440,473,477,485,504,506,533

%N Numbers of the form 3^x-y^2 >= 0.

%H Vincenzo Librandi, <a href="/A051214/b051214.txt">Table of n, a(n) for n = 1..1331</a>

%t max = 1000; Clear[f]; f[m_] := f[m] = Select[Table[3^x - y^2, {x, 0, m}, {y, 0, Ceiling[3^(x/2)]}] // Flatten // Union, 0 <= # <= max &]; f[1]; f[m = 2]; While[f[m] != f[m - 1], m++]; Print["m = ", m]; A051214 = f[m] (* _Jean-François Alcover_, May 14 2017 *)

%Y Cf. A201124.

%K nonn

%O 1,3

%A _David W. Wilson_