49283072

Appears in sequences

• Number of permutations of {1,2,...,n} that result in a binary search tree (when elements of the permutation are inserted in that order) of height n-1 (i.e., the second largest possible height).at n=20A076616
• a(n) is the smallest positive integral multiple of 2^n not in the range of the Euler phi function.at n=20A181662