Lah numbers: a(n) = n! * binomial(n-1, 3)/4!.

A001755

Lah numbers: a(n) = n! * binomial(n-1, 3)/4!.

Terms

    a(0) =1a(1) =20a(2) =300a(3) =4200a(4) =58800a(5) =846720a(6) =12700800a(7) =199584000a(8) =3293136000a(9) =57081024000

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