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 A281258 Digital root of n*(n+1)*(n+2)/2. 2

%I

%S 0,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,

%T 9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,

%U 6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9,3,3,3,6,6,6,9,9,9

%N Digital root of n*(n+1)*(n+2)/2.

%C Also zero together with period 9: repeat [3, 3, 3, 6, 6, 6, 9, 9, 9].

%C Also the decimal expansion of 334001/1001001.

%F a(n) = A010888(A027480(n)).

%t PadRight[{0},120,{9,3,3,3,6,6,6,9,9}] (* _Harvey P. Dale_, Mar 22 2018 *)

%Y Cf. A010888, A027480.

%K nonn,base

%O 0,2

%A _Peter M. Chema_, Jan 18 2017

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Last modified May 8 15:28 EDT 2021. Contains 343666 sequences. (Running on oeis4.)