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.

A144962 Eigentriangle, row sums = A000084.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 3, 1, 2, 4, 5, 3, 2, 4, 10, 17, 5, 6, 4, 10, 24, 41, 17, 10, 12, 10, 24, 66, 127, 41, 34, 20, 30, 24, 66, 180, 365, 127, 82, 68, 50, 72, 66, 180, 522, 1119, 365, 254, 164, 170, 120, 198, 180, 522, 1532
Offset: 1

Views

Author

Gary W. Adamson, Sep 27 2008

Keywords

Comments

Row sums = A000084: (1, 2, 4, 10, 24, 66,...).
Right border = A000084 shifted: (1, 1, 2, 4, 10, 24,...)
Left border = A001572: (1, 1, 1, 3, 5, 17, 41,...).
A000084 = the INVERT transform of A001572.
Sum of n-th row terms = rightmost term of next row.

Examples

			First few rows of the triangle =
1;
1, 1;
1, 1, 2;
3, 1, 2, 4;
5, 3, 2, 4, 10;
17, 5, 6, 4, 10, 24;
41, 17, 10, 12, 10, 24, 66;
127, 41, 34, 20, 30, 24, 66, 180;
365, 127, 82, 68, 50, 72, 66, 180, 522;
1119, 365, 254, 164, 170, 120, 198, 180, 522, 1532;
...
Example: row 5 = (5, 3, 2, 4, 10) = termwise products of (5, 3, 1, 1, 1) and (1, 1, 2, 4, 10).
		

Crossrefs

Formula

Triangle read by rows, T(n,k) = A001572(n-k+1) * (A000084 * 0^(n-k)), 1<=k<=n.
Given an A001572 "decrescendo" triangle: (1; 1,1; 1,1,1; 3,1,1,1; 5,3,1,1,1;...), where A001572 begins: (1, 1, 1, 3, 5, 17, 41, 127,...); apply termwise products of the decrescendo triangle row terms to A000084 terms: (1, 2, 4, 10, 24, 66, 180, 522,...).