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A037139 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)). 0
123, 285, 734, 1437, 2733, 926875, 2122173, 21466939, 797141342 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Here s(k) = sigma(k) - k (see A001065).
a(10) > 10^10, if it exists. - Amiram Eldar, Mar 14 2024
LINKS
PROG
(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
CROSSREFS
Sequence in context: A004945 A004965 A216382 * A269751 A235133 A179612
KEYWORD
nonn,more
AUTHOR
EXTENSIONS
More terms from Jason Earls, Aug 30 2001
Offset corrected, wrong term removed and a(8)-a(9) added by Amiram Eldar, Mar 14 2024
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)