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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.

A159907 Numbers m with half-integral abundancy index, sigma(m)/m = k+1/2 with integer k.

Table of values

n a(n)
1 2
2 24
3 4320
4 4680
5 26208
6 8910720
7 17428320
8 20427264
9 91963648
10 197064960
11 8583644160
12 10200236032
13 21857648640
14 57575890944
15 57629644800
16 206166804480
17 17116004505600
18 1416963251404800
19 15338300494970880
20 75462255348480000
21 88898072401645056
22 301183421949935616
23 6219051710415667200

List of values

[2, 24, 4320, 4680, 26208, 8910720, 17428320, 20427264, 91963648, 197064960, 8583644160, 10200236032, 21857648640, 57575890944, 57629644800, 206166804480, 17116004505600, 1416963251404800, 15338300494970880, 75462255348480000, 88898072401645056, 301183421949935616, 6219051710415667200]

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

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