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A198481
Square root of the largest square dividing ((2n-1)!)^(2n-3).
2
1, 1, 240, 304819200, 3440500260470784000, 1827912356210202139164672000000000, 13482302715547740229948201750717130814259200000000000
OFFSET
1,3
COMMENTS
For the complementary squarefree parts see A197880.
FORMULA
a(n) = A000188(A134367(2*n-1)). - R. J. Mathar, Oct 25 2011
MAPLE
A000188 := proc(n)
a := 1 ;
for pf in ifactors(n)[2] do
p := op(1, pf) ;
e := op(2, pf) ;
a := a*p^(floor(e/2)) ;
end do:
a ;
end proc:
A198481 := proc(n)
A000188( A134367(2*n-1)) ;
end proc:
seq(A198481(n), n=1..10) ; # R. J. Mathar, Oct 25 2011
MATHEMATICA
aa = {}; data = Table[kk = Sqrt[(n!)^(n - 2)], {n, 1, 100, 2}]; sp = data /. Sqrt[_] -> 1; sfp = data/sp; sp
Sqrt[#]&/@Table[Max[Select[Divisors[((2n-1)!)^(2n-3)], IntegerQ[Sqrt[#]]&]], {n, 7}] (* Harvey P. Dale, May 24 2024 *)
CROSSREFS
Sequence in context: A270051 A028678 A159950 * A306151 A075046 A153423
KEYWORD
nonn
AUTHOR
Artur Jasinski, Oct 25 2011
STATUS
approved