Update on 8014320

[Tim Buktu]

> On Dec 23, 2013, at 11:37 AM, Tim Buktu wrote:
>> * Compact storage of DFT vectors. At the moment, they are stored as
>> numbers modulo 2^2^(n+1) when (2^2^n)+1 would suffice. This will save
>> memory and may speed up the DFT and IDFT steps.
It did indeed improve performance. The latest patched BigInteger.java is at
https://github.com/tbuktu/bigint/blob/034daddfad1fd528daa363ed026a58b3ebe389b9/src/main/java/java/math/BigInteger.java

>> * Maybe add a multiplyParallel() method, now that dft() and idft() use
>> Bailey's algorithm which should make them easy to parallelize.
I checked an initial implementation into a separate Git branch:
https://github.com/tbuktu/bigint/blob/ef47eef52017c0db2cdda70dbdeda9fe3c8d0861/src/main/java/java/math/BigInteger.java

Tim