A309913 Distance from n to closest squarefree number that is different from n.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1

Offset

0,18

Links

Table of n, a(n) for n=0..100.

Index entries for sequences related to distance to nearest element of some set

Mathematica

a[n_] := Module[{k = 1}, While[! SquareFreeQ[n + k] && ! SquareFreeQ[n - k], k++]; k]; Table[a[n], {n, 0, 100}]

Crossrefs

Cf. A005117, A051700, A080733, A316190.

Sequence in context: A374540 A135362 A373387 * A317905 A227195 A111620

Adjacent sequences: A309910 A309911 A309912 * A309914 A309915 A309916

Keyword

nonn

Author

Ilya Gutkovskiy, Aug 22 2019

Status

approved