Numero difettivo

Un numero difettivo è un numero naturale maggiore della somma dei suoi divisori propri.

Per esempio, 10 è difettivo poiché la somma dei suoi divisori propri è 8 (=1+2+5).

Tutti i numeri primi e le loro potenze sono numeri difettivi. Tutti i divisori propri dei numeri difettivi e dei numeri perfetti sono a loro volta numeri difettivi.

Voci correlate

Altri progetti

Collegamenti esterni

(EN) Sequenza A005100, su On-Line Encyclopedia of Integer Sequences, The OEIS Foundation.

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Drvenik VeliFoto satelit Drvenik VeliGeografiLokasiLaut AdriatikKoordinat43°26′39″N 16°08′44″E / 43.444226°N 16.145439°E / 43.444226; 16.145439Koordinat: 43°26′39″N 16°08′44″E / 43.444226°N 16.145439°E / 43.444226; 16.145439Luas12.07 km2Titik tertinggi178 mPemerintahanNegara KroasiaKabupatenSplit-DalmatiaKependudukanPenduduk150 jiwa (2011) Pulau Drvenik Veli (bahasa Italia: Zirona Grande) ...

 

 

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Pour les articles homonymes, voir Saint-Martin. Cet article est une ébauche concernant une commune de la Vendée. Vous pouvez partager vos connaissances en l’améliorant (comment ?). Le bandeau {{ébauche}} peut être enlevé et l’article évalué comme étant au stade « Bon début » quand il comporte assez de renseignements encyclopédiques concernant la commune. Si vous avez un doute, l’atelier de lecture du projet Communes de France est à votre disposition pour vo...