(50g) OEIS A028842: Product of Digits is a Prime Sequence

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(50g) OEIS A028842: Product of Digits is a Prime Sequence - Gerald H - 09-07-2017 05:00 AM

For integer input N the programme returns the Nth element of the series

https://oeis.org/A028842

where the elements are all numbers in naturally ascending order whose product of digits is a prime.

Size: 267.5

CkSum: # DCE9h

Code:
::
  CK1&Dispatch
  # FF
  ::
    FPTR2 ^ZAbs
    DUP
    ZINT 1
    FPTR2 ^RADDext
    ZINT 2
    FPTR2 ^ZQUOText
    '
    ID SQRT0
    EvalNoCK
    DUP
    ZINT 4
    FPTR2 ^RMULText
    UNROTDUP
    ZINT 1
    FPTR2 ^RSUBext
    FPTR2 ^RMULText
    DUP
    FPTR2 ^RADDext
    FPTR2 ^RSUBext
    SWAP
    ZINT 4
    FPTR2 ^ZQUOText
    "# Digits"
    >TAG
    SWAP
    ZINT 4
    FPTR2 ^IDIV2
    SWAP
    ZINT 1
    FPTR2 ^RADDext
    SWAP
    ::
      ZINT 3
      EQUALcasedrop
      ZINT 4
      DUP
      ZINT 0
      EQUAL
      NOT?SEMI
      DROP
      ZINT 1
      FPTR2 ^RSUBext
      ZINT 6
    ;
    ZINT 1
    FPTR2 ^RADDext
    "Digit"
    >TAG
    SWAP
    "Pos"
    >TAG
    SWAP
  ;
;