1572860

Appears in sequences

• Start with 1, then alternately double or add 2.at n=37A099942
• Binomial transform of [1, 1, 5, 1, 5, 1, 5, ...].at n=19A131128
• a(n) is one fourth of the total number of free ends of 4 line segments expansion at n iterations (see Comments lines for definition).at n=37A238549
• Expansion of x*(1 - x + 4*x^2) / ((1 - x)*(1 - 2*x)).at n=20A296954
• a(n) is the number of times that only 2 pegs have disks on them during the optimal solution to a Towers of Hanoi problem with n disks.at n=37A347789