cp's OEIS Frontend

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.

A328562 Unitary weird numbers (A064114) that are not weird numbers (A006037).

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%I A328562 #10 Oct 20 2019 07:16:12
%S A328562 5390,11830,17010,20230,25270,37030,51030,58870,67270,93170,95830,
%T A328562 117670,129430,153090,153790,154630,196630,243670,260470,314230,
%U A328562 343910,352870,373030,436870,459270,480130,482230,554470,658630,714070,742630,801430,831670,851690,893830
%N A328562 Unitary weird numbers (A064114) that are not weird numbers (A006037).
%C A328562 All the terms are nonsquarefree, since unitary weird numbers that are squarefree are necessarily also weird.
%C A328562 Nonsquarefree unitary weird numbers that are also weird numbers are listed in A328563.
%H A328562 Amiram Eldar, <a href="/A328562/b328562.txt">Table of n, a(n) for n = 1..10000</a>
%t A328562 weirdQ[n_, d_, s1_, m1_] := weirdQ[n, d, s1, m1] = Module[{s = s1, m = m1}, If[m == 0, False, While[d[[m]] > n, s -= d[[m]]; m--]; d[[m]] < n && If[s > n, weirdQ[n - d[[m]], d, s - d[[m]], m - 1] && weirdQ[n, d, s - d[[m]], m - 1], s < n && m < Length[d] - 1]]];
%t A328562 wQ[n_] := Module[{d = Divisors[n]}, s = Total@d - n; m = Length[d] - 1; weirdQ[n, d, s, m]];
%t A328562 uQ[n_] := Module[{d = Select[Divisors[n], GCD[#, n/#] == 1 &]}, s = Total@d - n; m = Length[d] - 1; weirdQ[n, d, s, m]];
%t A328562 aQ[n_] := uQ[n] && ! wQ[n]; Select[Range[10^6], aQ]
%t A328562 (* after _M. F. Hasler_'s pari code at A006037 *)
%Y A328562 Cf. A005117, A006037, A013929, A064114, A292705, A328563.
%K A328562 nonn
%O A328562 1,1
%A A328562 _Amiram Eldar_, Oct 19 2019