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 A218562 Numbers n such that n^2 + 1 is divisible by a cube. 4

%I

%S 57,68,182,193,239,307,318,432,443,557,568,682,693,807,818,932,943,

%T 1057,1068,1182,1193,1307,1318,1432,1443,1557,1568,1682,1693,1807,

%U 1818,1932,1943,1958,1985,2057,2068,2182,2193,2307,2318,2432,2436,2443,2557,2568

%N Numbers n such that n^2 + 1 is divisible by a cube.

%e 239 is in the sequence because 239^2+1 = 2 * 13 ^ 4;

%e 1985 is in the sequence because 1985^2+1 = 2 * 17 ^ 3 * 401.

%t Select[Range[2,2600],Max[Transpose[FactorInteger[#^2+1]][[2]]]>2&]

%Y Cf. A002522, A049532, A034939.

%K nonn

%O 1,1

%A _Michel Lagneau_, Nov 02 2012

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Last modified January 28 00:32 EST 2020. Contains 331313 sequences. (Running on oeis4.)