50978

Appears in sequences

• a(n) = a(n-1) + 2*a(n-2) + (-1)^n.at n=16A006904
• a(0)=1, a(n)=2^n+n-2*a(n-1).at n=16A082383
• G.f.: 2*q * Product_{n>=1} (1 + q^(2*n))/((1 + q^n)*(1 + q^(2*n-1))*(1 + q^(4*n))) in powers of q.at n=36A293132