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A216954 Triangle read by rows: A216953/2. 2

%I

%S 1,1,1,1,0,3,1,1,0,6,1,0,0,0,15,1,1,3,0,0,27,1,0,0,0,0,0,63,1,1,0,6,0,

%T 0,0,120,1,0,3,0,0,0,0,0,252,1,1,0,0,15,0,0,0,0,495,1,0,0,0,0,0,0,0,0,

%U 0,1023,1,1,3,6,0,27,0,0,0,0,0,2010,1,0,0,0,0,0,0,0,0,0,0,0,4095,1,1,0,0,0,0,63,0,0,0,0,0,0,8127

%N Triangle read by rows: A216953/2.

%H B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="http://arxiv.org/abs/1212.6102">On Curling Numbers of Integer Sequences</a>, arXiv:1212.6102 [math.CO], 2012-2013.

%H B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Sloane/sloane3.html">On Curling Numbers of Integer Sequences</a>, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.

%e Triangle begins:

%e 1;

%e 1, 1;

%e 1, 0, 3;

%e 1, 1, 0, 6;

%e 1, 0, 0, 0, 15;

%e 1, 1, 3, 0, 0, 27;

%e 1, 0, 0, 0, 0, 0, 63;

%e 1, 1, 0, 6, 0, 0, 0, 120;

%e 1, 0, 3, 0, 0, 0, 0, 0, 252;

%e 1, 1, 0, 0, 15, 0, 0, 0, 0, 495;

%e ...

%t a027375[n_] := DivisorSum[n, MoebiusMu[n/#] 2^# &];

%t T[n_, k_] := If[Divisible[n, k], a027375[k]/2, 0];

%t Table[T[n, k], {n, 1, 14}, {k, 1, n}] // Flatten (* _Jean-Fran├žois Alcover_, Oct 06 2018 *)

%Y Cf. A216953. Main diagonal is A000740.

%K nonn,tabl

%O 1,6

%A _N. J. A. Sloane_, Sep 25 2012

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Last modified August 8 11:31 EDT 2020. Contains 336298 sequences. (Running on oeis4.)