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A064320
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a(n) = Product_{j=1..n} j^C(n-1,j-1).
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4
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1, 2, 12, 864, 14929920, 37150418534400000, 10063619980174622195712000000000000000, 664903611914043473202543232567979684173499596800000000000000000000000000000000000
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OFFSET
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1,2
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COMMENTS
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Product variant of binomial transform of natural numbers.
Array interpretation (first row and column are the natural numbers):
1 2 3 4 .....
2 2 6 12 ....
3 4 12 72 ...
....... 864 ...
(End)
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LINKS
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FORMULA
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Main diagonal of array T(i, 1)=i, T(1, j)=j and T(i, j)=T(i-1, j)*T(i-1, j-1). - Benoit Cloitre, Aug 16 2003, corrected Apr 16 2015
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EXAMPLE
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a(5) = (1^1)*(2^4)*(3^6)*(4^4)*(5^1) = 1*16*729*256*5 = 14929920.
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MAPLE
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MATHEMATICA
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Table[Product[j^Binomial[n - 1, j - 1], {j, 1, n}], {n, 8}] (* Michael De Vlieger, Apr 16 2015 *)
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PROG
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(PARI) a(n) = prod(j=1, n, j^binomial(n-1, j-1)); \\ Michel Marcus, Apr 17 2015
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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