bit_packed_mod6_sieve

Rererence code for bit packed mod6 sieve

Pre-requisites

• cc
• golang
• make

Reference implementations

Reference implementations are provided in c and golang

c

• Mod-6 wheel bit-packed unoptimized
• Mod-6 wheel bit-packed optimized

golang

• Mod-6 wheel bit-packed unoptimized
• Mod-6 wheel bit-packed optimized

How to run

make -C c/prime ./c/prime/prime to get results in a file named bits

$ ./c/prime/prime
$ ls -al bits
-rw-r--r-- 1 pgp pgp 4 Feb 16 23:44 bits
$ xxd bits
00000000: fede b769

How to decipher the result

$ xxd -b bits
00000000: 11111110 11011110 10110111 01101001

1's represent prime numbers following a mod-6 wheel starting at 5

1. 11111110 is 5 7 11 13 17 19 23 - 25 is a multiple of 5 marked by 0.
2. 11011110 is 29 31 37 41 43 47  - 35 and 49 are marked by 0.
3. 10110111 is 53 59 61 67 71 73  - 55 and 65 are marked by 0.
4. 01101001 is 79 83 89 97        - 77, 85, 91 and 95 are marked by 0.

How to run utils

• utils