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A176890 Triangle T(n,k) read by rows. Signed subsequence of A051731. 4
-1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Let A=A176890*A176890, B=A*A, C=B*B, D=C*C and so on, then the leftmost column in the last matrix converges to the Moebius function A008683.

LINKS

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

FORMULA

T(n,k) = if n=1 and k=1 then -1 elseif n=k then 0 elseif k divides n then 1 else 0.

EXAMPLE

Table begins:

-1,

1,0,

1,0,0,

1,1,0,0,

1,0,0,0,0,

1,1,1,0,0,0,

1,0,0,0,0,0,0,

1,1,0,1,0,0,0,0,

1,0,1,0,0,0,0,0,0,

1,1,0,0,1,0,0,0,0,0,

PROG

(Excel) =if(and(row()=1; column()=1); -1; if(mod(row(); column())=0; 1; 0)-if(and(column()>1; row()=column()); 1; 0))

CROSSREFS

Cf. A051731, A008683.

This is A176918 * the diagonalized mu(n).

Sequence in context: A318963 A295896 A176918 * A164057 A140820 A275661

Adjacent sequences:  A176887 A176888 A176889 * A176891 A176892 A176893

KEYWORD

sign,tabl

AUTHOR

Mats Granvik and Gary W. Adamson, Apr 28 2010

STATUS

approved

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Last modified November 21 12:20 EST 2019. Contains 329370 sequences. (Running on oeis4.)