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A138718
Group number of the elements of the n-th column of the periodic table of the elements with 18 columns.
3
1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 1, 2, 3, 4, 5, 6, 7, 8
OFFSET
1,2
EXAMPLE
Columns of The Periodic Table of the Elements:
1...2...3...4...5...6...7...8...9...10..11..12..13..14..15..16..17..18.
A notation convention of the groups is
1A, 2A, 3B, 4B, 5B, 6B, 7B, 8B, 8B, 8B, 1B, 2B, 3A, 4A, 5A, 6A, 7A, 8A.
Then the sequence of this entry is formed from the numeric characters: 1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 1, 2, ...
Note that the elements, of the 4th period, whose crystals are ferromagnetics (26=Fe=Iron, 27=Co=Cobalt and 28=Ni=Nickel) are in the group 8B.
CROSSREFS
Sequence in context: A063278 A355459 A110011 * A328289 A108922 A373195
KEYWORD
easy,fini,full,nonn
AUTHOR
Omar E. Pol, Mar 27 2008
STATUS
approved