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), ....