A078694 - OEIS

A078694

Numbers n such that floor(2*Pi*n) is prime.

5, 6, 7, 18, 21, 25, 26, 40, 41, 42, 49, 61, 62, 69, 70, 83, 91, 103, 104, 105, 110, 113, 127, 131, 132, 145, 148, 154, 167, 169, 174, 188, 189, 190, 196, 197, 210, 231, 237, 252, 258, 259, 272, 274, 279, 280, 294, 315, 323, 336, 339, 344, 357, 364, 365, 379

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OFFSET

1,1

COMMENTS

This sequence gives the radii of circles of positive integer radius which have the integer parts of their circumferences prime.

LINKS

Table of n, a(n) for n=1..56.

MATHEMATICA

Select[Range[10^3], PrimeQ[Round[2 Pi # ]] &]

CROSSREFS

Sequence in context: A342630 A347807 A161925 * A221175 A048007 A273402

Adjacent sequences: A078691 A078692 A078693 * A078695 A078696 A078697

KEYWORD

easy,nonn

AUTHOR

Joseph L. Pe, Dec 17 2002

STATUS

approved