Threaded Mode | Linear Mode

Gerald H · (This post was last modified: 06-15-2017 01:42 PM by Gene.)

For positive integer input N the programme returns the Nth element of the series of factors of the Natural Numbers.

For info on the series see

https://oeis.org/A027750

The time characteristic of the programme is linear on the input.

Code:

::

  CK1&Dispatch

  BINT1

  ::

    "  NTH FACTOR OF NATURAL SEQUENCE"

    DispCoord1

    SetDA3Temp

    COERCE

    ZEROZERO

    BEGIN

    SWAP#1+SWAP

    OVER

    FPTR2 ^#>Z

    FPTR2 ^DIVISext

    DUPLENCOMP

    ROT#+

    DUPUNROT

    5PICK

    #<

    WHILE

    DROP

    REPEAT

    '

    Z<

    FPTR2 ^SortList

    ROTDROPSWAP

    ROT

    #1--

    NTHCOMPDROP

  ;

;