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.

A051153 (-1)-sigma super perfect numbers: (-1)sigma((-1)sigma(x))=2*x, where if x=Product p(i)^r(i) then (-1)sigma(x)=Product (-1+Sum p(i)^s(i), s(i)=1 to r(i)); (-1)sigma(1)=1.

Table of values

n a(n)
1 247
2 988
3 2808
4 10440
5 87696
6 151200
7 191052
8 263520
9 2630320
10 3961980

List of values

[247, 988, 2808, 10440, 87696, 151200, 191052, 263520, 2630320, 3961980]

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

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