순열

순열 - 조합

n = ¹ ³⁰       r = ⁰ ³⁰

[순열]

$n!$ = $r!$ =

      $_{n} P_{r}$ = (비중복) $r \leq n$

$_{n} Π_{r}$ = (중복)

[조합]

      $_{n} C_{r}$ = (비중복) $r \leq n$

$_{n} H_{r}$ = (중복) $_{n + r - 1} C_{r}$

[같은 것이 있는 순열]

      n = $= p + q + r + s$       p = q = r = s =

      $\frac{n!}{p! q! r! s!}$ =

[순열]
	$n!$	=	$r!$ =
	$_{n} P_{r}$	=	(비중복)	$r \leq n$
	$_{n} Π_{r}$	=	(중복)

[조합]
	$_{n} C_{r}$	=	(비중복)	$r \leq n$
	$_{n} H_{r}$	=	(중복)	$_{n + r - 1} C_{r}$