*HEADING
EB3ARXE3: EIGENVALUE ANALYSIS OF AN UNCONSTRAINED PATCH OF ELEMENTS  [B33]
*NODE
 101,
 104,10.0
*NGEN
 101,104
*ELEMENT,TYPE=B33
 101,101,102
*ELGEN,ELSET=ALL
 101,3,1,1
*BEAM SECTION,SECTION=RECT,ELSET=ALL,MATERIAL=MAT
 0.1,0.1
*MATERIAL,NAME=MAT
*ELASTIC
 30E6,0.0
*DENSITY
7.5E-4, 
*STEP,PERTURBATION
*FREQUENCY, eigensolver=lanczos
10, , ,-1.E4
*NODE PRINT
 U,
*END STEP