increment cogs

[hxtree]

increment cogs by 1,3,7,and 9 iterates through all possibilities

• ones:
  0 1 2 3 4 5 6 7 8 9 0
• three:
  0 3 6 9 2 5 8 1 4 7 0
  *sevens:
  0 7 4 1 8 5 2 9 6 3 0
  *nines:
  0 9 8 7 6 5 4 3 2 1 0