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A277174 a(n) = Product_{i=1..n} i*rad(i) where rad(n) = A007947(n). 2
1, 1, 4, 36, 288, 7200, 259200, 12700800, 203212800, 5486745600, 548674560000, 66389621760000, 4780052766720000, 807828917575680000, 158334467844833280000, 35625255265087488000000, 1140008168482799616000000, 329462360691529089024000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Robert Israel, Table of n, a(n) for n = 0..268

FORMULA

a(n) = n! * A048803(n). - Robert Israel, Oct 02 2016

MAPLE

A277174 := proc(n) local rad, i;

rad := n -> mul(k, k in numtheory:-factorset(n));

mul(i * rad(i), i=1..n) end:

seq(A277174(i), i=0..17);

MATHEMATICA

Table[Product[i Last@ Select[Divisors@ i, SquareFreeQ], {i, n}], {n, 0, 17}] (* Michael De Vlieger, Oct 02 2016 *)

PROG

(PARI) a(n) = prod(i=1, n, i*factorback(factorint(i)[, 1])); \\ Michel Marcus, Oct 03 2016

CROSSREFS

Cf. A007947, A048803.

Sequence in context: A098916 A316297 A180170 * A059416 A240889 A108019

Adjacent sequences:  A277171 A277172 A277173 * A277175 A277176 A277177

KEYWORD

nonn

AUTHOR

Peter Luschny, Oct 02 2016

STATUS

approved

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Last modified October 20 15:15 EDT 2019. Contains 328267 sequences. (Running on oeis4.)