This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A111687 Comprimorial(n): the product of the first n primes and the first n composite numbers. 2
 8, 144, 5760, 362880, 39916800, 6227020800, 1482030950400, 422378820864000, 155435406077952000, 81137281972690944000, 50305114823068385280000, 39087074217524135362560000, 35256540944206770097029120000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..215 FORMULA a(n) = A002110(n)*A036691(n) for n>=1. - Rick L. Shepherd, Aug 20 2005 EXAMPLE a(1) = 2*4 = 8, a(2) = (2*3)*(4*6)=144. MATHEMATICA Module[{nn=50, prs, coms, len}, prs=Select[Range[nn], PrimeQ]; coms=Complement[ Range[4, nn], prs]; len=Min[Length[prs], Length[coms]]; Rest[FoldList[ Times, 1, Times@@@Thread[{Take[prs, len], Take[coms, len]}]]]] (* Harvey P. Dale, Jan 11 2014 *) CROSSREFS Cf. A002110 (primorials), A036691 (compositorials). Sequence in context: A052764 A024284 A024285 * A231851 A071305 A172150 Adjacent sequences:  A111684 A111685 A111686 * A111688 A111689 A111690 KEYWORD nonn AUTHOR Amarnath Murthy, Aug 17 2005 EXTENSIONS Corrected and extended by Rick L. Shepherd, Aug 20 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 15 22:28 EST 2019. Contains 320138 sequences. (Running on oeis4.)