Fieldguide Notes:

This khipus has 2 interesting field-marks:
1. Top cord set 1 equals the sum of cords 9 through 16 which equals 51
2. Top cord set 2 equals the number of grouped cords (7 groups of 3 cords each)

Ascher Databook Notes:
1. All cords have end knots making this a well-preserved specimen.
2. Association by color gives one possible grouping while spacing gives another: by color groups of 4,3,7,3,1,2; by spacing groups of 6,3,3,6,3,2.
3. Top cord P18 has value of 21 equaling the number of grouped cords (7 groups of 3 cords each) - excluding last two set off by main cord knot.
4. The value of top cord P1 plus the value of its subsidiary P1s1 equals 51. The total value of the first 7 pendants is 51 (I could not replicate this conclusion -  Ashok) and the total value of the next 7 pendants is 51.    Ashok added:   That is:

P1 + P1s1 = 51
$\sum\limits_{i=2}^{8} P_{i} = 58\;$
$\sum\limits_{i=9}^{16} P_{i} = 51\;$