55160

Appears in sequences

• One-half the number of permutations of length n with exactly 1 rising or falling successions.at n=9A000130
• Triangle read by rows: T(n,k) is one-half the number of permutations of length n with exactly n-k rising or falling successions, for n >= 1, 1 <= k <= n. T(1,1) = 1 by convention.at n=43A010028
• Number of ways to color vertices of a pentagon using <= n colors, allowing rotations and reflections.at n=14A060446
• Triangle read by rows: T(n,k) = one-half number of permutations of length n with exactly k rising or falling successions, for n >= 1, 0 <= k <= n-1. T(1,0) = 1 by convention.at n=37A086856
• Triangle read by rows related to double factorial of odd numbers (A001147).at n=31A230696
• G.f.: Sum_{n>=0} (n+1)*(n+2)*(n+3)/3! * x^n * (1 + x^n)^n.at n=39A326004
• Nonunitary weird numbers: numbers that are nonunitary abundant but not nonunitary pseudoperfect.at n=18A327948