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 A073915 Triangle read by rows in which the n-th row contains the first n numbers with n divisors. 7
 1, 2, 3, 4, 9, 25, 6, 8, 10, 14, 16, 81, 625, 2401, 14641, 12, 18, 20, 28, 32, 44, 64, 729, 15625, 117649, 1771561, 4826809, 24137569, 24, 30, 40, 42, 54, 56, 66, 70, 36, 100, 196, 225, 256, 441, 484, 676, 1089, 48, 80, 112, 162, 176, 208, 272, 304, 368, 405 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The first row contains the 1. The 2nd row contains the beginning of A000040. The 3rd contains the beginning of A001248, the 4th through 7th A030513 to A030516. The 8th through 20th rows come from A030626 to A030638. - R. J. Mathar, Mar 23 2007 LINKS T. D. Noe, Rows n = 1..100 of triangle, flattened EXAMPLE 1; 2,3; 4,9,25; 6,8,10,14; 16,81,625,2401,14641; ... MATHEMATICA d = Table[Length[Divisors[n]], {n, 2000}]; t = {}; n = 0; ok = True; While[ok, n++; If[PrimeQ[n], AppendTo[t, Prime[Range[n]]^(n - 1)], c = Flatten[Position[d, n, 1, n]]; If[Length[c] >= n, AppendTo[t, c], ok = False]]]; Flatten[t] (* T. D. Noe, Jun 23 2013 *) CROSSREFS Cf. A073916. Sequence in context: A088220 A333431 A085612 * A076381 A282571 A063455 Adjacent sequences:  A073912 A073913 A073914 * A073916 A073917 A073918 KEYWORD nonn,tabl AUTHOR Amarnath Murthy, Aug 18 2002 EXTENSIONS Corrected and extended by Sascha Kurz, Jan 28 2003 STATUS approved

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Last modified May 6 13:04 EDT 2021. Contains 343585 sequences. (Running on oeis4.)