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A121975 Number of isomeric aza-benzenoids with seven nitrogen atoms. 0
2, 100, 2276, 38500, 525764, 6229444, 66405417, 652844870, 6018548260 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Table of n, a(n) for n=2..10.

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 A126135

Adjacent sequences:  A121972 A121973 A121974 * A121976 A121977 A121978

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi, Sep 05 2006

STATUS

approved

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Last modified December 7 03:27 EST 2019. Contains 329836 sequences. (Running on oeis4.)