A216954 - OEIS

A216954

Triangle read by rows: A216953/2.

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, 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, 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

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OFFSET

1,6

LINKS

Table of n, a(n) for n=1..105.

B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, arXiv:1212.6102 [math.CO], 2012-2013.

B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.

EXAMPLE

Triangle begins:

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, 0, 0, 120;

1, 0, 3, 0, 0, 0, 0, 0, 252;

1, 1, 0, 0, 15, 0, 0, 0, 0, 495;

...

MATHEMATICA

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

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

Table[T[n, k], {n, 1, 14}, {k, 1, n}] // Flatten (* Jean-François Alcover, Oct 06 2018 *)

CROSSREFS

Cf. A216953. Main diagonal is A000740.

Sequence in context: A288108 A287822 A162169 * A124801 A124926 A175946

Adjacent sequences: A216951 A216952 A216953 * A216955 A216956 A216957

KEYWORD

nonn,tabl

AUTHOR

N. J. A. Sloane, Sep 25 2012

STATUS

approved