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A046038
Numbers k for which [ (4/3)^k ] is composite.
4
5, 8, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82
OFFSET
1,1
REFERENCES
Richard K. Guy, Unsolved Problems in Number Theory, 3rd Edition, Springer, 2004, Section E19, p. 338.
LINKS
Eric Weisstein's World of Mathematics, Floor Function.
MATHEMATICA
Select[Range[100], CompositeQ[Floor[(4/3)^#]]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 01 2019 *)
CROSSREFS
Cf. A070762.
Sequence in context: A259912 A078412 A144650 * A070127 A070128 A263263
KEYWORD
nonn
STATUS
approved