A375514 Numbers k such that floor((k^3 - k)/4) is squarefree.

2, 3, 4, 5, 10, 11, 12, 13, 14, 18, 20, 21, 26, 29, 30, 34, 40, 42, 43, 46, 50, 52, 56, 59, 60, 61, 62, 66, 67, 68, 69, 74, 77, 78, 82, 83, 84, 85, 88, 90, 92, 93, 94, 98, 104, 106, 110, 114, 115, 122, 123, 126, 130, 131, 132, 133, 138, 139, 140, 141, 142, 146

Offset: 1

Author

Juri-Stepan Gerasimov, Aug 18 2024

Keywords

• nonn

Crossrefs

Supersequence of A179017 and A269844.

Cf. A005117.

Programs

Magma

[k: k in [2..150] | IsSquarefree(Floor((k^3-k) div 4))];

Mathematica

Select[Range[150],SquareFreeQ[Floor[(#^3-#)/4]] &] (* Stefano Spezia, Aug 19 2024 *)