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A152453
Where records occur in A152235.
2
1, 2, 4, 12, 48, 144, 576, 720, 2880, 25920, 129600, 414720, 907200, 14515200, 58060800, 130636800, 522547200, 3265920000, 13063680000, 22861440000, 91445760000, 251475840000, 1005903360000, 16094453760000, 64377815040000, 81478172160000, 1030045040640000
OFFSET
1,2
LINKS
EXAMPLE
First few terms of A152235 are 1, 2, 2, 3, 2, 2, 2, 2, 3, 2, 2, 6, so a(1) to a(4) are 1, 2, 4, 12.
PROG
(Magma) W:=[]; r:=0; for n in [1..1300000] do a:=&*PrimeDivisors(NumberOfDivisors(n)); if r lt a then r:=a; Append(~W, n); end if; end for; print W;
CROSSREFS
Cf. A152235 (largest squarefree number dividing the number of divisors of n), A152452 (records in A152235), A007947 (largest squarefree number dividing n).
Subsequence of A025487.
Sequence in context: A332235 A131387 A207647 * A368814 A277281 A172452
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Dec 04 2008
EXTENSIONS
a(15)-a(20) from Donovan Johnson, Jul 30 2011
More terms from Amiram Eldar, Sep 01 2019
STATUS
approved