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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A382930 a(n) is the smallest k such that A382506(k) + sigma(k) = A000396(n).

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%I A382930 #24 Apr 24 2025 23:25:03
%S A382930 1,4,16,180,2520,7207200
%N A382930 a(n) is the smallest k such that A382506(k) + sigma(k) = A000396(n).
%C A382930 Numbers k for which A382506 "jumps", there appears to be a remarkable relationship to A002182, the highly composites, in line with jumps for A382483 being in that series. See also the graph for A382506.
%e A382930 A382506(16) = 465, 465 + sigma(16) = 496, which is perfect.
%Y A382930 Cf. A002093, A002182, A382506.
%K A382930 nonn,more
%O A382930 1,2
%A A382930 _Leo Hennig_, Apr 09 2025
%E A382930 New name and a(1) from _Jinyuan Wang_, Apr 10 2025
%E A382930 a(6) from _David A. Corneth_, Apr 10 2025