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A328562 Unitary weird numbers (A064114) that are not weird numbers (A006037). 2
5390, 11830, 17010, 20230, 25270, 37030, 51030, 58870, 67270, 93170, 95830, 117670, 129430, 153090, 153790, 154630, 196630, 243670, 260470, 314230, 343910, 352870, 373030, 436870, 459270, 480130, 482230, 554470, 658630, 714070, 742630, 801430, 831670, 851690, 893830 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All the terms are nonsquarefree, since unitary weird numbers that are squarefree are necessarily also weird.

Nonsquarefree unitary weird numbers that are also weird numbers are listed in A328563.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

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]]];

wQ[n_] := Module[{d = Divisors[n]}, s = Total@d - n; m = Length[d] - 1; weirdQ[n, d, s, m]];

uQ[n_] := Module[{d = Select[Divisors[n], GCD[#, n/#] == 1 &]}, s = Total@d - n; m = Length[d] - 1; weirdQ[n, d, s, m]];

aQ[n_] := uQ[n] && ! wQ[n]; Select[Range[10^6], aQ]

(* after M. F. Hasler's pari code at A006037 *)

CROSSREFS

Cf. A005117, A006037, A013929, A064114, A292705, A328563.

Sequence in context: A224688 A335936 A335939 * A340109 A190106 A252572

Adjacent sequences:  A328559 A328560 A328561 * A328563 A328564 A328565

KEYWORD

nonn

AUTHOR

Amiram Eldar, Oct 19 2019

STATUS

approved

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Last modified July 4 23:17 EDT 2022. Contains 355086 sequences. (Running on oeis4.)