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.

A290052 Number of X-rays of n X n binary matrices with exactly n ones.

Table of values

n a(n)
0 1
1 1
2 4
3 23
4 139
5 860
6 5393
7 34142
8 217717
9 1396346
10 8997695
11 58205686
12 377775385
13 2458841504
14 16043226825
15 104901986083
16 687221188145
17 4509605878736
18 29636894936761
19 195035340954186
20 1285062484293880
21 8476508261617168
22 55969236979211755
23 369900194873712830

List of values

[1, 1, 4, 23, 139, 860, 5393, 34142, 217717, 1396346, 8997695, 58205686, 377775385, 2458841504, 16043226825, 104901986083, 687221188145, 4509605878736, 29636894936761, 195035340954186, 1285062484293880, 8476508261617168, 55969236979211755, 369900194873712830]

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

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