A071221 Product of next n composite numbers.

4, 48, 1080, 60480, 5544000, 622702080, 106661318400, 28405593216000, 8247280940236800, 3294906785089920000, 1595754032207182848000, 840201424492187197440000, 653671274699431372640256000

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..224

Example

a(1) = 4,a(2) = 6*8 = 48 and a(3) = 9*10*12 = 1080.

Mathematica

nn=15; With[{comps=Complement[Rest[Range[(nn(nn+1))]], Prime[Range[ PrimePi[ (nn(nn+1))]]]]}, Table[Times@@Take[comps, {(n(n-1))/2+1, (n(n+1))/2}], {n, nn}]] (* Harvey P. Dale, Dec 03 2012 *)
Module[{nn=200, cmps, len}, cmps=Select[Range[nn], CompositeQ]; len=Floor[(Sqrt[8 Length[cmps]+1]-1)/2]; Times@@@TakeList[cmps, Range[len]]] (* Harvey P. Dale, May 25 2022 *)

Crossrefs

Sequence in context: A052714 A144828 A138448 * A198038 A024255 A211045

Adjacent sequences: A071218 A071219 A071220 * A071222 A071223 A071224

Keyword

nonn

Author

Amarnath Murthy, May 17 2002

Extensions

Corrected and extended by Lior Manor Jun 02 2002

Status

approved