278239

Appears in sequences

• a(n) = 2*a(n-1) - 3*a(n-2) + 2*a(n-3) with a(0) = 1, a(1) = 5, a(2) = 6.at n=39A105577
• Branched catafusenes (cata-condensed benzenoids) without helicenes, symmetry C_s.at n=9A323923