A Goldbach partition of an even number is an unordered pair of primes
such that
(Oliveira e Silva). Letting
denote the number of Goldbach partitions of
without regard to order, the number of ways of writing
as a sum of two prime
numbers taking the order of the two primes into
account, for
, is
|
(1)
|
The Goldbach conjecture is then equivalent to the statement that or, equivalently, that
, for every even
integer
.
The
and
convention above is used by Oliveira e Silva. The NIST Digital Library of Mathematical
Functions instead denotes by
the number of unordered partitions into odd
primes for even integers
. In analytic
number theory, Bhowmik and Halupczok (2020) use
, where the sum is over primes,
for the ordered unweighted count. They use
for the weighted count, where
is the Mangoldt function, while Brüdern
et al. (2019) denote this weighted function by
. Veritasium (2025) uses
for the unordered partition count. This
is a local notation for Goldbach partitions and is unrelated
to the standard functions
and
that count prime factors.
For an even integer , each Goldbach partition determines a unique
larger prime number
in the interval
. Consequently,
|
(2)
|
where
is the prime counting function. Equality
holds iff
is a prime number for every
prime number
in that interval. Deshouillers
et al. (1993, p. 210) proved that 210 is the largest value of
attaining this upper bound.
Here
. Numberphile (2017) illustrates the equality
case.
A plot of , sometimes known as Goldbach's comet, for
up to 2000 is illustrated above.
For an integer , the cumulative number
of Goldbach partitions is
|
(3)
|
where
is the
th
prime number (J. F. Martin, pers. comm., Dec. 4,
2010). The initial 1 counts
. For each smaller odd
prime
, the summand counts
the possible primes
with
, so every
remaining partition is counted exactly once.
The following table summarizes the values of several variants of for
, 4, ....
| partition type | OEIS | values |
| A001031 | 1, 2, 2, 2, 2, 2, 3, 2, 3, 3, 3, 4, 3, ... | |
| A045917 | 0, 1, 1, 1, 2, 1, 2, 2, 2, 2, 3, 3, 3, ... | |
| A002375 | 0, 0, 1, 1, 2, 1, 2, 2, 2, 2, 3, 3, 3, ... |
Various fractal properties have been observed in Goldbach's partition (Liang et al. 2006).