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 A166475 4th level primorials: product of first n superduperprimorials. 7
 1, 2, 48, 414720, 270888468480000, 30900096179361042923520000000000, 1848494880770448654906901042987600267878400000000000000000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Next term has 110 digits. a(n) = first counting number with n distinct positive tetrahedral exponents in its prime factorization (cf. A000292). 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 LINKS FORMULA a(n) = Product_{k=1..n} prime(k)^((n-k+1)^2). EXAMPLE 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. CROSSREFS Subsequence of A025487. Cf. A002110, A006939, A066120 for first, second and third level primorials. Sequence in context: A191954 A212170 A057527 * A152688 A046873 A261125 Adjacent sequences:  A166472 A166473 A166474 * A166476 A166477 A166478 KEYWORD nonn,easy AUTHOR Matthew Vandermast, Nov 05 2009 EXTENSIONS Offset corrected by Matthew Vandermast, Nov 07 2009 Edited by Matthew Vandermast, Nov 10 2009, May 23 2012 Name changed by Arkadiusz Wesolowski, Feb 21 2014 STATUS approved

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Last modified December 7 22:29 EST 2019. Contains 329850 sequences. (Running on oeis4.)