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 A354697 a(n) is the least integer that can be written in two or more ways as the product of the integers in two subsets of its A070824(a(n)) nontrivial divisors, each of size n and with empty intersection. 1
 12, 120, 720, 10080, 110880, 1814400, 26611200, 518918400, 10378368000, 261534873600, 5928123801600, 168951528345600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS a(6) <= 110880 = 2*3*6*10*14*22 = 4*5*7*8*9*11. LINKS Table of n, a(n) for n=2..13. FORMULA A070824(a(n)) >= 2*n. EXAMPLE a(2) = 12 = 2*6 = 3*4, a(3) = 120 = 2*3*20 = 4*5*6, a(4) = 720 = 2*4*9*10 = 3*5*6*8, a(5) = 10080 = 2*3*6*10*28 = 4*5*7*8*9. a(6) = 110880 = 2*3*6*10*14*22 = 4*5*7*8*9*11. a(7) = 1814400 = 2*3*4*14*15*18*20 = 5*6*7*8*9*10*12. CROSSREFS Cf. A002182, A025487. Sequence in context: A188251 A093334 A001816 * A133386 A305624 A056320 Adjacent sequences: A354694 A354695 A354696 * A354698 A354699 A354700 KEYWORD nonn,hard,more AUTHOR Hugo Pfoertner, Jun 03 2022 EXTENSIONS a(6) confirmed by and a(7)-a(13) from David A. Corneth, Jun 04 2022 STATUS approved

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Last modified March 2 14:21 EST 2024. Contains 370493 sequences. (Running on oeis4.)