login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A121949
Number of isomeric aza-benzenoids with one nitrogen atom and n hexagons.
1
1, 2, 10, 43, 210, 1026, 5130, 25770, 130350, 661458
OFFSET
1,2
REFERENCES
N. Trinajstich, Z. Jericevic, J. V. Knop, W. R. Muller and K. Szymanski, "Computer generation of isomeric structures", Pure and Appl. Chem., vol. 55 (1983) pp. 379-390.
EXAMPLE
If n=5 then the number of isomeric aza-benzenoids with one nitrogen atom is 210. Here n is the number of hexagons.
CROSSREFS
Sequence in context: A197048 A175613 A296001 * A376225 A005144 A305657
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Sep 04 2006
STATUS
approved