19280

Appears in sequences

• Number of rooted maps with n edges on Klein bottle.at n=3A006344
• a(n) = Sum_{k=0..floor(n/2)} T(n-k,k), T given by A026725.at n=20A026735
• Numbers k such that k-th and (k+1)-st term of A038593 differ by 4.at n=10A038635
• Expansion of (1 - sqrt( 1 - 4*x*sqrt( 1 + 4*x )) )/( 2*x ).at n=8A081698
• a(n) = ceiling(Sum_{i=1..n-1} a(i)/4) for n >= 2 starting with a(1) = 1.at n=47A120160
• Triangle read by rows: T(n,k) = number of rooted maps with n edges on a nonorientable surface of genus k (1 <= k <= n).at n=11A267180
• Number of locally disjoint rooted identity trees with n nodes, meaning no branch overlaps any other branch of the same root.at n=16A316471
• a(n) = (2*n^4 - 6*(-1)^n*n^2 - 2*n^2 + 3*(-1)^n - 3)/96.at n=31A350050
• Number of distinct edges among all circles that can be constructed on vertices of an n-sided regular polygon, using only a compass.at n=15A359047
• Truncate Stirling's asymptotic series for 4! after n terms and round to the nearest integer.at n=77A362116
• a(n) is the sigma irregularity of the n-th power of a path graph of length at least 3*n.at n=14A363706
• a(n) = (3*n^4 - 4*n^3 + n^2 + 4*n + 4)/4.at n=13A366478