Zeisel Number
A number
where the
s are distinct primes and
such that
 |
(1)
|
for
, 2, ...,
,
taken as 1, and with
and
some fixed integers. For example,
is a Zeisel number with
since
 |
(2)
|
as is
since
 |
(3)
|
The first few Zeisel numbers are 105, 1419, 1729, 1885, 4505, ... (OEIS A051015), which correspond to constants (1, 2), (4,
), (1, 6), (2, 3), (3, 2), ....
REFERENCES:
MathPages. "Zeisel Numbers." https://www.mathpages.com/home/kmath015.htm.
Sloane, N. J. A. Sequence A051015 in "The On-Line Encyclopedia of Integer Sequences."