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.

A128257 Inverse Moebius transform of A097807.

Original entry on oeis.org

1, 0, 1, 2, -1, 1, -1, 2, -1, 1, 2, -1, 1, -1, 1, 0, 1, 0, 1, -1, 1, 2, -1, 1, -1, 1, -1, 1, -2, 3, -2, 2, -1, 1, -1, 1, 3, -2, 2, -1, 1, -1, 1, -1, 1, 0, 1, 0, 0, 0, 1, -1, 1, -1, 1, 2, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -2, 3, -2, 3, -2, 2, -1, 1, -1, 1, -1, 1, 2, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1
Offset: 0

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Author

Gary W. Adamson, Feb 21 2007

Keywords

Comments

Row sums = A001227: (1, 1, 2, 1, 2, 2, 2,...), number of odd divisors of n.

Examples

			First few rows of the triangle are:
1;
0, 1;
2, -1, 1;
-1, 2, -1, 1;
2, -1, 1, -1, 1;
0, 1, 0, 1, -1, 1;
...
		

Crossrefs

Formula

A051731 * A097807 as infinite lower triangular matrices.

Extensions

a(18) = 1 corrected and more terms from Georg Fischer, Jun 08 2023