407779

Appears in sequences

• a(n) = sum(2^(A047240(i)-1), i=1..n).at n=9A113854
• a(0) = 0, a(n+1) = 2*a(n) + (-1)^floor(n/3).at n=19A275788
• a(n) is the number whose base-4 digits are 1 followed by the first n-1 terms of the periodic sequence with initial period 2,0,3.at n=9A378497