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A168184
Characteristic function of numbers that are not multiples of 10.
17
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1
OFFSET
0,1
FORMULA
a(n+10) = a(n);
a(n) = A000007(A010879(n));
a(A067251(n)) = 1; a(A008592(n)) = 0;
not the same as A168046: a(n)=A168046 for n<=100;
A033442(n) = Sum_{k=0..n} a(k)*(n-k).
Dirichlet g.f.: (1-1/10^s)*zeta(s). - R. J. Mathar, Feb 19 2011
For the general case: the characteristic function of numbers that are not multiples of m is a(n)=floor((n-1)/m)-floor(n/m)+1, m,n > 0. - Boris Putievskiy, May 08 2013
MATHEMATICA
Table[If[Mod[n, 10]==0, 0, 1], {n, 0, 110}] (* or *) PadRight[{}, 110, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1}] (* Harvey P. Dale, Jun 03 2023 *)
PROG
(Haskell)
a168184 = (1 -) . (0 ^) . (`mod` 10)
a168184_list = cycle [0, 1, 1, 1, 1, 1, 1, 1, 1, 1]
-- Reinhard Zumkeller, Oct 10 2012
(PARI) a(n)=n%10>0 \\ Charles R Greathouse IV, Sep 24 2015
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Nov 30 2009
STATUS
approved