32688

Appears in sequences

• Numbers k that divide the (left) concatenation of all numbers <= k written in base 7 (most significant digit on left).at n=11A029476
• Triangle read by rows: T(n,k) is the number of hex trees with n edges and k pairs of adjacent vertices of outdegree 2.at n=14A126188
• Number of hex trees with n edges and no adjacent vertices of outdegree 2.at n=8A126189
• 11th column of A172119.at n=15A172320
• Arises in enumerating Huffman codes, compact trees, and sums of unit fractions.at n=17A194633
• Number of binary words of length n which have no 0^b 1 1 0^a 1 0 1 0^b - matches, where a=b=2.at n=15A234592
• a(0) = 0; thereafter a(n) = a(n-1)/2 + n if a(n-1) is even, otherwise a(n) = a(n-1) + a(n-2).at n=36A350129
• Expansion of Product_{k>=1} 1/(1 - (2^k - 1) * x^k).at n=11A382977