cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A176891 Triangle T(n,k) = k if k

Original entry on oeis.org

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

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Author

Gary W. Adamson and Mats Granvik, Apr 28 2010

Keywords

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.

Examples

			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

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.

Extensions

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