47 lines
1.3 KiB
Plaintext
47 lines
1.3 KiB
Plaintext
The sequence is generated by following this pseudo-code:
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<pre>
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A: The first term is zero.
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Repeatedly apply:
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If the last term is *new* to the sequence so far then:
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B: The next term is zero.
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Otherwise:
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C: The next term is how far back this last term occured previously.
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</pre>
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;Example:
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Using A:
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:<code>0</code>
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Using B:
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:<code>0 0</code>
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Using C:
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:<code>0 0 1</code>
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Using B:
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:<code>0 0 1 0</code>
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Using C: (zero last occurred two steps back - before the one)
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:<code>0 0 1 0 2</code>
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Using B:
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:<code>0 0 1 0 2 0</code>
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Using C: (two last occurred two steps back - before the zero)
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:<code>0 0 1 0 2 0 2 2</code>
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Using C: (two last occurred one step back)
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:<code>0 0 1 0 2 0 2 2 1</code>
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Using C: (one last appeared six steps back)
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:<code>0 0 1 0 2 0 2 2 1 6</code>
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...
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;Task:
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# Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
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# Use it to display here, on this page:
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:# The first ten terms of the sequence.
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:# Terms 991 - to - 1000 of the sequence.
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;References:
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* [https://www.youtube.com/watch?v=etMJxB-igrc Don't Know (the Van Eck Sequence) - Numberphile video].
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* [[wp:Van_Eck%27s_sequence|Wikipedia Article: Van Eck's Sequence]].
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* [[OEIS:A181391| OEIS sequence: A181391]].
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<br><br>
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