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A056606 Squarefree kernel of A002944(n), the LCM of binomial coefficients {C(n,0),...,C(n,n)}. 4
1, 2, 3, 6, 10, 30, 105, 70, 42, 210, 2310, 2310, 4290, 6006, 15015, 30030, 170170, 510510, 1939938, 1385670, 881790, 9699690, 223092870, 44618574, 17160990, 74364290, 31870410, 223092870, 6469693230, 6469693230, 100280245065 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also squarefree kernel of A001142; row products in table A256113. - Reinhard Zumkeller, Mar 21 2015

a(2372) has 1001 decimal digits. - Michael De Vlieger, Jul 14 2017

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..2371

EXAMPLE

a(7)=105 because LCM[1,7,21,35]=105 is already squarefree.

MATHEMATICA

Table[Apply[Times, FactorInteger[Product[k^(2 k - 1 - n), {k, n}]][[All, 1]]], {n, 31}] (* or *)

Table[Apply[Times, FactorInteger[Apply[LCM, Range@ n]/n][[All, 1]]], {n, 2, 32}] (* Michael De Vlieger, Jul 14 2017 *)

PROG

(Haskell)

a056606 = a007947 . a001142  -- Reinhard Zumkeller, Mar 21 2015

CROSSREFS

Cf. A002944, A034386, A048633, A003418, A000142, A001405.

Cf. A007947, A001142, A256113.

Sequence in context: A327711 A274964 A054357 * A186408 A062527 A296444

Adjacent sequences:  A056603 A056604 A056605 * A056607 A056608 A056609

KEYWORD

nonn

AUTHOR

Labos Elemer, Aug 07 2000

STATUS

approved

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Last modified October 14 14:36 EDT 2019. Contains 328019 sequences. (Running on oeis4.)