9!/2!-[7!+(7!/2!-5!)+7!-5!-5!+3!]=169194
long before i did it on tiit.....
29. The number of permutations of the word
HINDUSTAN such that none of the three
patterns HIN, DUS, TAN occurs is
(1) 169194 (2) 166680
(3) 169190 (4) 166670
9!/2!-[7!+(7!/2!-5!)+7!-5!-5!+3!]=169194
long before i did it on tiit.....