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 A225070 Least decagonal (10-gonal) number that is the product of n decagonal numbers greater than 1. 7
 10, 69300, 9729720, 4257000, 967412160, 4104100000, 1408951239696000, 59860503846000000, 1542547619019487080000, 39054496014386012160000, 450510331438947780000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Lars Blomberg, Table of n, a(n) with solutions for n=1..11 EXAMPLE Let dec(n) = n*(4n-3). Then a(1) = 10 = dec(2). a(2) = 69300 = dec(132) = dec(2) * dec(42). a(3) = 9729720 = dec(1560) = dec(3) * dec(4) * dec(42). a(4) = 4257000 = dec(1032) = dec(2)^3 * dec(33). a(5) = 967412160 = dec(15552) = dec(2) * dec(3) * dec(4) * dec(8) * dec(9). a(6) = 4104100000 = dec(32032) = dec(2)^3 * dec(4) * dec(7) * dec(11). CROSSREFS Cf. A001107 (decagonal numbers). Cf. A212616, A212617, A225066-A225069 (3-, 5- to 9-gonal cases). Sequence in context: A260797 A055310 A048832 * A115673 A225720 A013792 Adjacent sequences:  A225067 A225068 A225069 * A225071 A225072 A225073 KEYWORD nonn,more AUTHOR T. D. Noe, May 01 2013 EXTENSIONS Corrected a(6) and added a(7)-a(11) by Lars Blomberg, Sep 20 2013 STATUS approved

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Last modified October 22 00:52 EDT 2019. Contains 328315 sequences. (Running on oeis4.)