A176891 Triangle T(n,k) = k if k<n and k|n, = 0 otherwise, 1 <= k <= n; read by rows.

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

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