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A132350
If n > 1 is a k-th power with k >= 2 then a(n) = 0, otherwise a(n) = 1.
6
1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0
OFFSET
1,1
LINKS
FORMULA
a(n) = 1 - A075802(n) for n >= 2. - R. J. Mathar, Nov 12 2007
Given the Möbius function mu(n) = A008683(n), a(n) = abs(mu(n)) unless n is in A303946. - Alonso del Arte, May 28 2018
EXAMPLE
a(4) = 0 because 4 = 2^2.
a(8) = 0 because 8 = 2^3.
a(12) = 1 because 12 is not a perfect power (though it is divisible by a perfect power).
MATHEMATICA
Table[Boole[GCD@@FactorInteger[n][[All, 2]] == 1], {n, 100}] (* Alonso del Arte, May 28 2018 *)
PROG
(PARI) (a(n)=!ispower(n)); (r(nMax) = for(j=1, nMax, print1(!ispower(j)", "))); r(100)
(Haskell)
a132350 1 = 1
a132350 n = 1 - a075802 n -- Reinhard Zumkeller, Jun 14 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 11 2007
EXTENSIONS
Edited by M. F. Hasler, Jun 01 2018
STATUS
approved