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A218562
Numbers k such that k^2 + 1 is divisible by a cube.
5
57, 68, 182, 193, 239, 307, 318, 432, 443, 557, 568, 682, 693, 807, 818, 932, 943, 1057, 1068, 1182, 1193, 1307, 1318, 1432, 1443, 1557, 1568, 1682, 1693, 1807, 1818, 1932, 1943, 1958, 1985, 2057, 2068, 2182, 2193, 2307, 2318, 2432, 2436, 2443, 2557, 2568
OFFSET
1,1
LINKS
EXAMPLE
239 is in the sequence because 239^2 + 1 = 2 * 13 ^ 4.
1985 is in the sequence because 1985^2 + 1 = 2 * 17 ^ 3 * 401.
MATHEMATICA
Select[Range[2, 2600], Max[Transpose[FactorInteger[#^2+1]][[2]]]>2&]
CROSSREFS
Cf. A000578 (cubes).
Sequence in context: A334238 A336328 A056082 * A067809 A176636 A072054
KEYWORD
nonn
AUTHOR
Michel Lagneau, Nov 02 2012
STATUS
approved