A "visual representation" number which is a sum of some simple function of its digits. For example,
(1)
| |||
(2)
| |||
(3)
| |||
(4)
| |||
(5)
| |||
(6)
|
are all VR numbers given by Madachy (1979), where is a factorial and is a subfactorial.
A "visual representation" number which is a sum of some simple function of its digits. For example,
(1)
| |||
(2)
| |||
(3)
| |||
(4)
| |||
(5)
| |||
(6)
|
are all VR numbers given by Madachy (1979), where is a factorial and is a subfactorial.
Weisstein, Eric W. "VR Number." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/VRNumber.html