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A176891 Triangle T(n,k) = k if k<n and k|n, = 0 otherwise, 1 <= k <= n; read by rows. 3
1, 1, 0, 1, 0, 0, 1, 2, 0, 0, 1, 0, 0, 0, 0, 1, 2, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 2, 0, 4, 0, 0, 0, 0, 1, 0, 3, 0, 0, 0, 0, 0, 0, 1, 2, 0, 0, 5, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 0, 6, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

A variant of A127093, which has T(n,n) = n. [The original definition said "Subsequence of A127093". Since all nonnegative integers are repeated infinitely often in both sequences, each one is a subsequence of the other, but there is no such relation on a row-by-row basis. - M. F. Hasler, Aug 08 2016]

Let A=A176891*A176891, B=A*A, C=B*B, D=C*C and so on, then the leftmost column in the last matrix (D) converges to A165552.

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 k else 0.

EXAMPLE

Triangle begins:

1,

1,0,

1,0,0,

1,2,0,0,

1,0,0,0,0,

1,2,3,0,0,0,

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

1,2,0,4,0,0,0,0,

CROSSREFS

Cf. A127093, A165552.

Sequence in context: A216279 A025441 A286813 * A219486 A284574 A206499

Adjacent sequences:  A176888 A176889 A176890 * A176892 A176893 A176894

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson and Mats Granvik, Apr 28 2010

EXTENSIONS

Definition corrected by M. F. Hasler, Aug 08 2016

STATUS

approved

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Last modified May 21 00:41 EDT 2019. Contains 323427 sequences. (Running on oeis4.)