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A211206
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Least number which reaches n under the operation introduced in A100787: first differences are the digits of the sequence.
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1
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1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 5, 3, 3, 5, 3, 1, 1, 5, 3, 3, 11, 5, 1, 1, 3, 3, 5, 5, 19, 13, 1, 3, 1, 5, 7, 1, 7, 1, 7, 5, 5, 1, 13, 3, 1, 1, 11, 9, 1, 5, 3, 1, 3, 11, 1, 9, 20, 13, 3, 7, 1, 3, 5, 1, 5, 9, 3, 5, 9, 3, 11, 1, 7, 3, 11, 1, 5, 1
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OFFSET
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1,3
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COMMENTS
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E. Angelini proposes to call Wilsonize(n) the sequence starting with n and having as first differences the digits of the (concatenated) terms of the sequence. Then this sequence lists the smallest starting value a(n)=k such that n is a term of Wilsonize(k).
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LINKS
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PROG
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(PARI) A211206(n)={ for(k=1, n, my(seed=k, d=digits(seed)); while(seed<n, seed+=d[1]; d=vecextract(concat(d, digits(seed)), "^1")); seed==n&return(k))}
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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