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A152452 Records in A152235. 1
1, 2, 3, 6, 10, 15, 21, 30, 42, 70, 105, 110, 210, 330, 390, 462, 546, 770, 910, 1155 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..20.

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, 3, 6.

PROG

(MAGMA) R:=[]; r:=0; for n in [1..1300000] do a:=&*PrimeDivisors(NumberOfDivisors(n)); if r lt a then r:=a; Append(~R, a); end if; end for; print R;

CROSSREFS

Cf. A152235 (largest squarefree number dividing the number of divisors of n), A152453 (where records in occur in A152235), A007947 (largest squarefree number dividing n).

Sequence in context: A215891 A254033 A102366 * A217741 A074134 A056178

Adjacent sequences:  A152449 A152450 A152451 * A152453 A152454 A152455

KEYWORD

more,nonn

AUTHOR

Klaus Brockhaus, Dec 04 2008

EXTENSIONS

a(15)-a(18) from Sean A. Irvine, Mar 09 2011

a(19)-a(20) from Donovan Johnson, Jul 30 2011

STATUS

approved

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Last modified March 18 22:11 EDT 2019. Contains 321305 sequences. (Running on oeis4.)