0,2

Number of symmetric chiral (optically active) isomers possible for organic compounds with n distinct carbon atoms.

f := n -> if n mod 2 = 0 then 2^n-2^(n/2) else 2^n; fi;

Second differences of A027556.

Sequence in context: A046690 A008828 A053414 this_sequence A087955 A026537 A089248

Adjacent sequences: A014233 A014234 A014235 this_sequence A014237 A014238 A014239

nonn

Paul F. Hudrlik (hudrlik(AT)scs.howard.edu)