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A066120
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Superduperprimorials: product of first n terms in Chernoff sequence.
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8
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OFFSET
| 0,2
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COMMENTS
| First number with n distinct positive triangular exponents. Subsequence of A025487. [From Matthew Vandermast (ghodges14(AT)comcast.net), Nov 05 2009]
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LINKS
| Harry J. Smith, Table of n, a(n) for n=0,...,17
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FORMULA
| a(n) = Product_{1< = i< = n}[prime(i)^((n-i+1)(n-i+2)/2)] = a(n-1)*A006939(n) = A066119(n-3, 4).
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EXAMPLE
| a(4) = 2*(2*(2*3))*(2*(2*3)*(2*3*5)) =2*(2*6)*(2*6*30) =2*12*360 =8640
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PROG
| (PARI) { for (n=0, 17, a=1; for(i=1, n, a*=prime(i)^((n - i + 1)*(n - i + 2)/2)); write("b066120.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Feb 01 2010]
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CROSSREFS
| Cf. A000040, A002110, A006939, A055462.
Sequence in context: A203465 A055462 A088600 * A152687 A062716 A137888
Adjacent sequences: A066117 A066118 A066119 * A066121 A066122 A066123
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KEYWORD
| nonn
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AUTHOR
| Henry Bottomley (se16(AT)btinternet.com), Dec 05 2001
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