Threaded Mode | Linear Mode

Gerald H · (This post was last modified: 06-15-2017 01:43 PM by Gene.)

The Champernowne sequence

https://oeis.org/A030190

is the natural number sequence

https://en.wikipedia.org/wiki/ISO_80000-2

concatenated in binary & split into single digits:

0,1,1,0,1,1,1,0,0.........

For integer input N the programme returns the Nth element of the series starting from index zero.

Code:

::

  CK1&Dispatch

  BINT1

  ::

    FPTR2 ^PUSHFLAGS_

    %ABSCOERCE

    #1+

    DOBIN

    BINT64

    dostws

    BINT0

    BEGIN

    DUP

    #>HXS

    hxs>$

    LEN$

    #2-

    ROTSWAP

    2DUP

    #-

    4UNROLL

    DIFF_OR_ZERO_

    #0<>

    WHILE

    #1+

    REPEAT

    #>HXS

    hxs>$

    BINT3

    LAST$

    DUPLEN$

    FPTR2 ^POPFLAGS_

    ROTSWAP

    2DUP#>

    IT

    ::

      BINT0

      ROT

      #-SWAP

    ;

    SWAP#-

    DUP

    SUB$

    FPTR2 ^S>Z

  ;

;