seen from United States
seen from China
seen from France
seen from Spain
seen from Brazil
seen from Czechia
seen from Czechia
seen from Ireland
seen from Türkiye
seen from Türkiye
seen from Japan
seen from Germany
seen from T1
seen from United States
seen from Türkiye
seen from United States
seen from United States
seen from Türkiye
seen from United States
seen from Türkiye
!n
148.349 es el único número igual a la suma de subfactoriales de sus cifras.
Un subfactorial (!n) cuenta el número de formas diferentes en que n amigos pueden intercambiar regalos si cada uno da y recibe un regalo. Por ejemplo, en un amigo invisible con 4 personas, !4 = 9.
