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.

A059578 Variation of Boustrophedon transform applied to 1,1,1,1,... Fill an array by diagonals, all in the 'up' direction. The first column is 1,1,1,1,.... For the next element of a diagonal, add to the previous element the elements of the row and the column the new element is in. The first row gives a(n).

Table of values

n a(n)
1 1
2 2
3 7
4 30
5 147
6 792
7 4559
8 27500
9 171645
10 1099388
11 7185101
12 47724494
13 321225165
14 2186177302
15 15018795171
16 104011496474
17 725373340023
18 5089785834004
19 35907469451787
20 254541483884544
21 1812185157383017
22 12951828431246472
23 92893383046741073
24 668383820775639066

List of values

[1, 2, 7, 30, 147, 792, 4559, 27500, 171645, 1099388, 7185101, 47724494, 321225165, 2186177302, 15018795171, 104011496474, 725373340023, 5089785834004, 35907469451787, 254541483884544, 1812185157383017, 12951828431246472, 92893383046741073, 668383820775639066]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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