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A176309
Integers k such that k and k^3 +- 1 are nonsquarefree numbers.
1
49, 50, 68, 99, 116, 117, 124, 125, 128, 175, 176, 243, 244, 245, 275, 276, 315, 316, 324, 325, 343, 344, 351, 360, 361, 423, 424, 425, 459, 460, 472, 475, 476, 549, 604, 605, 700, 704, 716, 724, 725, 775, 776, 832, 833, 844, 845, 846, 847, 848, 867, 868
OFFSET
1,1
LINKS
EXAMPLE
49 = 7*7; 49^3 - 1 = 2^4 * 3^2 * 19 * 43; 49^3 + 1 = 2 * 5^2 * 13 * 181.
MATHEMATICA
f[n_]:=SquareFreeQ[n]; lst={}; Do[If[ !f[n^3-1]&&!f[n^3+1]&&!f[n], AppendTo[lst, n]], {n, 2*6!}]; lst
CROSSREFS
Sequence in context: A050709 A371969 A037412 * A080201 A042199 A257443
KEYWORD
nonn
AUTHOR
STATUS
approved