Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Minimal number of singular fibers in a nonorientable Lefschetz fibration   We show that there exists an admissible nonorientable genus $g$ Lefschetz
fibration with only one singular fiber over a closed orientable surface of
genus $h$ if and only if $g \geq 4$ and $h \geq 1$.

24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int