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 A194359 Triangle of divisors of 210^n, each number occurring once. 2
 1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 35, 42, 70, 105, 210, 4, 9, 12, 18, 20, 25, 28, 36, 45, 49, 50, 60, 63, 75, 84, 90, 98, 100, 126, 140, 147, 150, 175, 180, 196, 225, 245, 252, 294, 300, 315, 350, 420, 441, 450, 490, 525, 588, 630, 700, 735, 882, 900 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The length of row k is A005917, the rhombic dodecahedral numbers, (k+1)^4 - k^4. The triangle has rows beginning with 2^k and ending with 210^k. LINKS T. D. Noe, Rows n = 0..9 MATHEMATICA Join[{{1}}, Table[Complement[Divisors[210^n], Divisors[210^(n-1)]], {n, 9}]] CROSSREFS Cf. A018336, A194356, A194357, A194358. Sequence in context: A028722 A030050 A018336 * A277006 A220355 A059041 Adjacent sequences:  A194356 A194357 A194358 * A194360 A194361 A194362 KEYWORD nonn,tabf AUTHOR T. D. Noe, Aug 26 2011 STATUS approved

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Last modified July 17 18:47 EDT 2019. Contains 325109 sequences. (Running on oeis4.)