HP 50g Programming Competition: How Many Partitions of an Integer in 4 Squares

[Gerald H]

While nothing to do with this thread, Pari uses quite sophisticated methods to factorize.

While nothing to do with this thread:

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cached 78498 primes. pmax = 999983


>> factor((720^20-19)*(720^20+19))

fac: factoring 19647163408174555224851228006154190582188393911909356605589226111943416217599999​9999999999999999999999999
9999999639
fac: using pretesting plan: normal
fac: no tune info: using qs/gnfs crossover of 95 digits
div: primes less than 10000
fmt: 1000000 iterations
Total factoring time = 0.1200 seconds


***factors found***

P58 = 1401683395356260729391818575873415577600000000000000000019
P58 = 1401683395356260729391818575873415577599999999999999999981

ans = 1

>>

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