*HEADING
: EIGENVALUE ANALYSIS OF AN UNCONSTRAINED 1-ELEMENT MESH  [CPS4]
*PREPRINT,ECHO=YES
*RESTART,WRITE,FREQ=999
*PART,NAME=ONE_EL
*NODE,NSET=NALL
 1,0.,0.
 3,7.,0.
 7,0.,7.
 9,7.,7.
*ELEMENT,TYPE=CPS4, ELSET=EALL
 1,1,3,9,7
*SOLID SECTION,MATERIAL=A1, ELSET=EALL
*END PART
*ASSEMBLY, NAME=ASSEMBLY-1
*INSTANCE, NAME=ONE_EL-1, PART=ONE_EL
*END INSTANCE
*END ASSEMBLY
*MATERIAL,NAME=A1
*ELASTIC
 3.E6,.3
*DENSITY
 7.5E-4, 
*STEP
*FREQUENCY, eigensolver=lanczos, SIM=NO
 8, , ,-1.E7 
*EL FILE,MODE=8
 ENER,
 ELEN, 
*NODE FILE,MODE=8
 U, 
*MODAL FILE
*OUTPUT,FIELD,MODELIST
 8
*END STEP