Why does "cal 9 1752" produce incorrect results?

[Ken Henry]

Does anybody know why "cal 9 1752" produce incorrect
results?  It seems to be in the Unix systems I
checked (BSD 4.3, AIX 3.1).  

-Ken

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| Ken Henry, 203 Myrtle #102 | khenry at umaxc.weeg.uiowa.edu|319-335-5491 W|
| Iowa City, IA 52246        | khenrypb at uiamvs.bitnet     |319-338-5449 H|
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