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• Test Number

The mouth of a prime volcano (truncated pyramid).

          1069 
         310693
        33106933
       3331069333
      333310693333

1069 = 1 + 1*3 + 1*3*5 + 1*3*5*7 + 1*3*5*7*9. [Silva]

The first "double" super-2 emirp, i.e., an emirp p such that 2*p^2 contains twice 2 consecutive 2's in its decimal representation (2*p^2=2285522). [Loungrides]