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A081513
a(2)=0; for n != 2, let m = A081512(n), then a(n) = value of d_n in the lexicographically earliest set of n distinct divisors d_1, ..., d_n of m with d_1 + ... + d_n = m.
3
1, 0, 3, 6, 12, 8, 24, 20, 28, 40, 40, 30, 60, 45, 60, 120, 90, 72, 72, 168, 240, 180, 144, 168, 168, 216, 420, 315, 210, 420, 420, 336, 432, 1260, 840, 840, 504, 504, 315, 480, 540, 2520, 2520, 1680, 1680, 1260, 1260, 1008, 720, 2520, 2520, 1890, 1512, 945, 3360
OFFSET
1,3
LINKS
EXAMPLE
The lexicographically earliest solutions are:
..n....m: d_1 d_2 ... d_n
-------------------------
..1....1: 1
..2....0: - -
..3....6: 1, 2, 3
..4...12: 1, 2, 3, 6
..5...24: 1, 2, 3, 6, 12
..6...24: 1, 2, 3, 4, 6, 8
..7...48: 1, 2, 3, 4, 6, 8, 24
..8...60: 1, 2, 3, 4, 5, 10, 15, 20
..9...84: 1, 2, 3, 4, 6, 7, 12, 21, 28
.10..120: 1, 2, 3, 4, 5, 6, 15, 20, 24, 40
...
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Mar 27 2003
EXTENSIONS
Corrected by Caleb M. Shor (cshor(AT)bates.edu), Sep 26 2007
Terms a(8) onwards from Jinyuan Wang, May 23 2020
Definition clarified by N. J. A. Sloane, May 23 2020, following suggestions from Jinyuan Wang.
STATUS
approved