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A037139
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Deficient numbers k such that k-s(k)-s(k-s(k)) = s(s(k))-s(k) or s(k-s(k))-k+s(k) = s(k)-s(s(k)).
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0
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OFFSET
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1,1
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COMMENTS
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Here s(k) = sigma(k) - k (see A001065).
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LINKS
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PROG
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(PARI) s(n) = sigma(n) - n;
is(n) = {my(s1 = s(n)); if(s1 >= n, 0, n - s1 - s(n-s1) == s(s1) - s1); } \\ Amiram Eldar, Mar 14 2024
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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Offset corrected, wrong term removed and a(8)-a(9) added by Amiram Eldar, Mar 14 2024
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STATUS
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approved
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