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 A132066 Irregular array: the sum of the first m terms of row n is the m-th positive divisor of n. 0
 1, 1, 1, 1, 2, 1, 1, 2, 1, 4, 1, 1, 1, 3, 1, 6, 1, 1, 2, 4, 1, 2, 6, 1, 1, 3, 5, 1, 10, 1, 1, 1, 1, 2, 6, 1, 12, 1, 1, 5, 7, 1, 2, 2, 10, 1, 1, 2, 4, 8, 1, 16, 1, 1, 1, 3, 3, 9, 1, 18, 1, 1, 2, 1, 5, 10, 1, 2, 4, 14, 1, 1, 9, 11, 1, 22, 1, 1, 1, 1, 2, 2, 4, 12, 1, 4, 20, 1, 1, 11, 13, 1, 2, 6, 18, 1, 1, 2, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Row n contains A000005(n) terms. LINKS EXAMPLE The positive divisors of 20 are 1,2,4,5,10,20. Row 20 of the array is 1,1,2,1,5,10. So we have 1=1; 1+1=2; 1+1+2=4; 1+1+2+1=5; 1+1+2+1+5=10; 1+1+2+1+5+10=20. The first 10 rows: 1; 1,1; 1,2; 1,1,2; 1,4; 1,1,1,3 1,6; 1,1,2,4; 1,2,6; 1,1,3,5 MATHEMATICA f[n_] := Block[{d}, d = Divisors[n]; d - Prepend[Most[d], 0]]; Flatten[Array[f, 40]] (* Ray Chandler, Nov 01 2007 *) CROSSREFS Cf. A027750, A000005. Sequence in context: A046067 A342416 A305531 * A102190 A138650 A266685 Adjacent sequences:  A132063 A132064 A132065 * A132067 A132068 A132069 KEYWORD nonn,tabf AUTHOR Leroy Quet, Oct 30 2007 EXTENSIONS Extended by Ray Chandler, Nov 01 2007 STATUS approved

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Last modified July 29 09:31 EDT 2021. Contains 346344 sequences. (Running on oeis4.)