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A046037 Numbers n for which floor((3/2)^n) is composite. 0
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, E19.

LINKS

Table of n, a(n) for n=1..69.

Eric Weisstein's World of Mathematics, Floor Function

MATHEMATICA

Select[Range[100], CompositeQ[Floor[(3/2)^#]]&] (* Harvey P. Dale, Sep 23 2014 *)

PROG

(PARI) is(n)=n>7&&!isprime(floor(1.5^n)) \\ Charles R Greathouse IV, Oct 27 2011

CROSSREFS

Sequence in context: A004449 A168098 A020722 * A089017 A182361 A023391

Adjacent sequences:  A046034 A046035 A046036 * A046038 A046039 A046040

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified November 25 23:11 EST 2014. Contains 250013 sequences.