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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
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
Sequence in context: A224688 A335936 A335939 * A340109 A364991 A190106
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 19 2019
STATUS
approved

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Last modified March 29 07:27 EDT 2024. Contains 371265 sequences. (Running on oeis4.)