HEPTAGON
Example: NHEOATGP
That example has the vowel sequence EOA
The vowels {A,E,O} can be arranged together in any of 3! ways.
For each of those 3! ways, we can form the permutation of these 6 things:
H,P,T,G,N,(vowel sequence)
in 6! ways.
Answer: 3!6! = 6*120 = 720 ways.
Edwin