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A034882
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Product of consecutive factorials.
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3
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1, 2, 6, 12, 24, 120, 144, 288, 720, 2880, 5040, 17280, 34560, 40320, 86400, 362880, 2073600, 3628800, 12441600, 24883200, 39916800, 203212800, 435456000, 479001600, 6227020800, 10450944000, 14631321600, 62705664000, 87178291200
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OFFSET
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1,2
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COMMENTS
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It appears that only 3628800 and 53094139822080000 have more than one representation. We have 3628800 = 10! = 6! * 7! and 53094139822080000 = 8! * 9! * 10! = 6! * 7! * 8! * 9!. - T. D. Noe, Jun 13 2012
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LINKS
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MATHEMATICA
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Union[Reap[For[x1=1, x1 <= 14, x1++, x2=x1; a=x1!; While[a < 10^11, Sow[a]; x2 = x2+1; a = a*x2!]]][[2, 1]]] (* Jean-François Alcover, Jun 11 2012, after PARI *)
nn = 20; t = Range[nn]!; j = 2; While[i = 2; new = 0; While[p = Times @@ Take[t, {i, i + j - 1}]; p < t[[nn]], AppendTo[t, p]; new++; i++]; new > 0, j++]; t = Union[t] (* T. D. Noe, Jun 13 2012 *)
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PROG
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(PARI) l=listcreate(100)
for(x1=1, 14, x2=x1; a=x1!; while(a<1e11, listput(l, a); x2=x2+1; a=a*x2!))
listsort(l, 1); print(l)
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CROSSREFS
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KEYWORD
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easy,nonn,nice
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AUTHOR
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STATUS
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approved
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