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4th level primorials: product of first n superduperprimorials.
7

%I #17 Jul 07 2023 21:06:50

%S 1,2,48,414720,270888468480000,30900096179361042923520000000000,

%T 1848494880770448654906901042987600267878400000000000000000000

%N 4th level primorials: product of first n superduperprimorials.

%C Next term has 110 digits.

%C a(n) = first counting number with n distinct positive tetrahedral exponents in its prime factorization (cf. A000292).

%C Note: a(n) is not the first counting number with n distinct square exponents in its prime factorization, as previously stated. That sequence is A212170. - _Matthew Vandermast_, May 23 2012

%H Dario Alpern, <a href="https://www.alpertron.com.ar/ecm.htm">Factorization using the Elliptic Curve Method</a>

%F a(n) = Product_{k=1..n} prime(k)^((n-k+1)^2).

%e a(3) = 414720 = 2^10*3^4*5^1 has 3 positive tetrahedral exponents in its prime factorization (cf. A000292). It is the smallest number with this property.

%Y Subsequence of A025487.

%Y Cf. A002110, A006939, A066120 for first, second and third level primorials.

%K nonn,easy

%O 0,2

%A _Matthew Vandermast_, Nov 05 2009

%E Offset corrected by _Matthew Vandermast_, Nov 07 2009

%E Edited by _Matthew Vandermast_, Nov 10 2009, May 23 2012

%E Name changed by _Arkadiusz Wesolowski_, Feb 21 2014