I think with H=1, we need to have at least 2 node

and with H=0, N(0)= 1

N(1)=2

And rest procedure is correct but your ans is for h=10 , so for h=11

N(11)= 1 + N(10) + N(9)

= 1 + 232 + 143

= 376

and with H=0, N(0)= 1

N(1)=2

And rest procedure is correct but your ans is for h=10 , so for h=11

N(11)= 1 + N(10) + N(9)

= 1 + 232 + 143

= 376