3587228

Appears in sequences

• a(n) = -2*a(n-1) + 3*a(n-2), with a(0)=1, a(1)=2.at n=15A084222
• Numbers occurring in A137822 : first differences of numbers n such that 3 | sum( Catalan(k), k=1..2n).at n=22A137823