The 1948 issue of the Surakarta notes contained lines to indicate the value of the notes, like five thin lines to represent the value “5” and 2 thick and one thin line to represent the value “2 ½”.
The 1949 issues do not contain this additional value indication. These notes have their value also printed in large red numbers on the obverse. These numbers show a mysterious pattern of vertical lines through the numbers. The number “5” and number “2” have one full vertical line from top to bottom and three small vertical lines on the bottom of each number. The note with the value “5” therefore has a pattern of one full line and three small lines. The note with the value “25” also has the same pattern when one divides the lines with the number of numbers (2 full lines and 6 small lines divided by two numbers = 1 full line and three small lines). The note with the value “10” has the same result: the number “1” with one full line and the number “0” with one full line and six small lines (2 full lines and 6 small lines divided by two numbers = 1 full lime and three small lines). An interesting observation is that no other possible denomination of notes, like 50, 100, 200, 250, 500 and 1000 can be constructed with these numbers while getting the same result or same pattern.
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