Let `n_1ltn_2ltn_3ltn_4ltn_5` be positive integers such that `n_1+n_2+n_3+n_4+n_5="20.` then the number of distinct arrangements `n_1, n_2, n_3, n_4, n_5` is

Let n_1ltn_2ltn_3ltn_4ltn_5 be positive integers such that n_1+n_2+n_3+n_4+n_5=20 . Then the numbr of distinct arrangments (n_1,n_2,n_3,n_4,n_5) is_________

Let n_1 le n_2< n_3 < n_4< n_5 be positive integers such that n_1+n_2+n_3+n_4+n_5=20. then the number of such distinct arrangements n_1, n_2, n_3, n_4, n_5 is

Let n_(1)ltn_(2)ltn_(3)ltn_(4)ltn_(5) be positive integers such that n_(1)+n_(2)+n_(3)+n_(4)+n_(5)=20 . Then the number of such distinct arrangements (n_(1),n_(2),n_(3),n_(4),n_(5)) is

Let n_(1)

If n and m (ltn) are two positive integers then n(n-1)(n-2)...(n-m) =

The number of positive integers 'n' for which 3n-4, 4n-5 and 5n - 3 are all primes is:

For a positive integer n let a(n)=1+1/2+1/3+1/4+….+1/ ((2^n)-1) Then

The greatest positive integer, which divides (n+1)(n+2)(n+3)(n+4) for all n in N is

The least positive integer n such that 2 divides n,3 divides n+1,4 divides n+2,5 divides n+3 and 6 divides n+4 is