help with combinatorics

[rotund forge]

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[orchid quarry]

yea it's wrong

doesnt make sense

it cant be simplified

any further

[abstract surge]

use the recursive definition of factorial

$(n+4)!=(n+4)(n+3)!=(n+4)(n+3)(n+2)!$

[wraith dust]

Omegabet_

[trim shoal]

Ohhhh