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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.

A342398 Numbers k such that there is a subset of the nontrivial unitary divisors of k, {d|k : 1 < d < k, gcd(d, k/d) = 1}, that adds up to k.

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%I A342398 #15 Mar 11 2021 03:32:33
%S A342398 30,42,66,78,102,114,138,150,174,186,210,222,246,258,282,294,318,330,
%T A342398 354,366,390,402,420,426,438,462,474,498,510,534,546,570,582,606,618,
%U A342398 630,642,654,660,678,690,714,726,750,762,770,780,786,798,822,834,840,858
%N A342398 Numbers k such that there is a subset of the nontrivial unitary divisors of k, {d|k : 1 < d < k, gcd(d, k/d) = 1}, that adds up to k.
%H A342398 Amiram Eldar, <a href="/A342398/b342398.txt">Table of n, a(n) for n = 1..10000</a>
%e A342398 30 is a term since its proper unitary divisors, 1 < d < 30, are {2, 3, 5, 6, 10, 15}, and 5 + 10 + 15 = 30.
%t A342398 q[n_] := Module[{d = Most @ Select[Divisors[n], CoprimeQ[#, n/#] &], x}, Plus @@ d >= n && SeriesCoefficient[Series[Product[1 + x^d[[i]], {i, 2, Length[d]}], {x, 0, n}], n] > 0]; Select[Range[1000], q]
%Y A342398 The unitary version of A136446.
%Y A342398 Subsequence of A034683 and A293188.
%K A342398 nonn
%O A342398 1,1
%A A342398 _Amiram Eldar_, Mar 10 2021