OFFSET
1,6
COMMENTS
a(n) = 1 iff n belongs to sequence A051532. - Avi Peretz (njk(AT)netvision.net.il), Feb 27 2001
LINKS
Eric M. Schmidt, Table of n, a(n) for n = 1..2000
MathOverflow, Center of p-groups
FORMULA
For prime p and m >= 2, a(p^m) = p^(m - 2). - Eric M. Schmidt, Sep 20 2012
EXAMPLE
a(6) = 3 because the commutator subgroup of the symmetric group S_3 is the group Z_3.
PROG
(GAP) A059807 := function(n) local max, fact, i; if (IsPrimePowerInt(n)) then fact := Factors(n); if (Length(fact) >= 2) then return n/fact[1]^2; fi; fi; max := 1; for i in [1..NumberSmallGroups(n)] do max := Maximum(max, Size(DerivedSubgroup(SmallGroup(n, i)))); od; return max; end; # Eric M. Schmidt, Sep 20 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Noam Katz (noamkj(AT)hotmail.com), Feb 24 2001
EXTENSIONS
More terms from Eric M. Schmidt, Sep 20 2012
STATUS
approved