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.

A131568 a(n) = sum of numbers which in base 2 contain exactly n digits 1 and not more than n digits 0.

Table of values

n a(n)
0 0
1 3
2 45
3 630
4 8925
5 128898
6 1891890
7 28113228
8 421717725
9 6372696330
10 96865261350
11 1479397776948
12 22684103302770
13 348986220258900
14 5384358887026500
15 83278084352019480
16 1290810308357922525
17 20045524792117559130
18 311819274557663622750
19 4857816066846093281700

List of values

[0, 3, 45, 630, 8925, 128898, 1891890, 28113228, 421717725, 6372696330, 96865261350, 1479397776948, 22684103302770, 348986220258900, 5384358887026500, 83278084352019480, 1290810308357922525, 20045524792117559130, 311819274557663622750, 4857816066846093281700]

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

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