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A329190
Weird admirable numbers: numbers that are both weird (A006037) and admirable (A111592).
4
70, 836, 4030, 5830, 7192, 7912, 10792, 17272, 45356, 83312, 91388, 113072, 243892, 254012, 388076, 786208, 1713592, 4145216, 4199030, 4632896, 9928792, 11547352, 13086016, 15126992, 17999992, 29465852, 29581424, 34869056, 74899952, 89283592, 95327216, 120888092
OFFSET
1,1
COMMENTS
Admirable numbers that are not pseudoperfect (A005835).
Differs from A258250 at n >= 13.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..66 (terms below 10^11)
MATHEMATICA
admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2]; weirdQ[n_] := Module[{d = Most[Divisors[n]]}, If[Total[d] <= n, False, SeriesCoefficient[Series[Product[1 + x^d[[i]], {i, Length[d]}], {x, 0, n}], n] == 0]]; Select[Range[10000], admQ[#] && weirdQ[#] &]
CROSSREFS
Intersection of A006037 and A111592.
Sequence in context: A006037 A002975 A354282 * A258250 A349285 A335008
KEYWORD
nonn
AUTHOR
Amiram Eldar, Nov 07 2019
STATUS
approved