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A121975
Number of isomeric aza-benzenoids with seven nitrogen atoms.
1
2, 100, 2276, 38500, 525764, 6229444, 66405417, 652844870, 6018548260
OFFSET
2,1
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 seven nitrogen atoms is 38500. Here n is the number of hexagons.
CROSSREFS
Sequence in context: A230816 A174646 A092699 * A102188 A225601 A332567
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Sep 05 2006
STATUS
approved