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A101648
Atomic numbers of the metalloids or semimetals on the periodic table.
5
5, 14, 32, 33, 51, 52, 84
OFFSET
1,1
COMMENTS
If ununhexium and ununseptium turn out to be metalloids, 116 and 117 should be added to this sequence, so I'm not putting the keyword full at this time. The metalloids are sandwiched between the nonmetals and the poor metals on the periodic table.
REFERENCES
The New Encyclopaedia Britannica, 15th Edition, 1991, Volume 15 (Macropedia), Chemical Elements.
EXAMPLE
The atomic number of boron is 5.
CROSSREFS
Cf. A099955, alkali metals; A099956, alkaline earth metals; A101647, nonmetals (except halogens and noble gases); A097478, halogens; A018227, noble gases; A101649, poor metals.
Sequence in context: A360487 A023652 A283523 * A265100 A070134 A295344
KEYWORD
fini,nonn
AUTHOR
Robert Happelberg (roberthappelberg(AT)yahoo.com), Dec 10 2004
STATUS
approved