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

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

Amiram Eldar, Table of n, a(n) for n = 1..10000

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. A002522, A049532, A034939.

Cf. A000578 (cubes).

Sequence in context: A334238 A336328 A056082 * A067809 A176636 A072054

Adjacent sequences: A218559 A218560 A218561 * A218563 A218564 A218565

Keyword

nonn

Author

Michel Lagneau, Nov 02 2012

Status

approved