सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

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Bhāskara adds that a Kshayamāsa occured in 974 Saka
i.e. 62 years before his birth which knowledge he must have
derived from hearsay or even by calculation. He then
predicted its recurrence in the Saka years 1115, 1256 and
1378 which were at intervals of 141 years, 141 years and
122 years respectively. In the year 974 Saka i.e. 4153
Kali year, applying the above formula Dwidhābdāḥ the
number of Adhikamāsās elapsed from the beginning of the
Kali were 1531-21-12-52-30 i.e. the S'uddhi at the begin-
ning of that year was 21-12-52-30. This naturally entailed
the occurence of a Kshayamāsa. Thereafter during the
years 1115, 1256 and 1378, the S'uddhis in the beginning of
the years should be as per the above analysis 21-12-52-30
plus 68-22-30 i.e. 21-19-15; 21-25-37-30 and 21-25-37-30
and 21-18-23 respectively so that Bhāskara could forecast
the occurrence of the Kshayamāsās in those years also. In
this context it is worth-noting that Gaṇeśa notified in a
verse that Kshayamāsās would recur in the years 1462,
1603, 1744, 1885, 2167, 2232, 2373, 2392, 2524, 2533, 2655,
2674, 2796, 2815 according to Sūrya Siddhānta and accord-
ing to Āryabhaṭīya during the years 1482, 1793, 1904, 2129,
2186, 2251. These years also may be verified by computing
the S'uddhis as said before and also with respect to Ārya-
bhaṭīya according to which the number of Adhimāsas
during a yuga differs by a little and as such effects a differ-
ence in the sequence of the Kshayamāsa years.
Verse 8. Tell me, how, when and in the course of
how many years do two Adhikamāsas occur as mentioned
by the Rishis? Questioned accordingly by an expert in
questioning, if a mathematician could know the answer, I
would reckon him as no other than Bhāskara (either the
Sun-god or he himself i.e. Bhāskarāchārya) who could make
the lotus-buds of mathematicians blossom.
Comm. Probably taking up this challenge alone
Gaṇeśa answered the question and gave the years cited
above which should bring in a recurrence of Kshayamāsās.
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