  We develop a Fourier-Chebyshev pseudospectral direct numerical simulation
(DNS) to examine a potentially singular solution of the radially bounded,
three-dimensional (3D), axisymmetric Euler equations [G. Luo and T.Y. Hou,
Proc. Natl. Acad. Sci. USA, 111.36 (2014)]. We demonstrate that: (a) the time
of singularity is preceded, in any spectrally truncated DNS, by the formation
of oscillatory structures called tygers, first investigated in the
one-dimensional (1D) Burgers and two-dimensional (2D) Euler equations; (b) the
analyticity-strip method can be generalized to obtain an estimate for the
(potential) singularity time.
