Solution found by (d)epth-first search
  starting state: [t,1,2,5,10,12,15]-[]
  with a limit of 100 steps.
    steps            *states* 
---------------------------------------
    (0-0) -- [t,1,2,5,10,12,15]-[]
    (0-2) -- [5,10,12,15]-[t,1,2]
    (0-3) -- [t,1,5,10,12,15]-[2]
    (0-8) -- [10,12,15]-[t,1,2,5]
    (0-9) -- [t,1,10,12,15]-[2,5]
    (0-19) -- [12,15]-[t,1,2,5,10]
    (0-20) -- [t,1,12,15]-[2,5,10]
    (0-32) -- [15]-[t,1,2,5,10,12]
    (0-33) -- [t,1,15]-[2,5,10,12]
    (0-48) -- []-[t,1,2,5,10,12,15]

datime(2002,3,20,1,44,5) -- datime(2002,3,20,1,44,5)



Solution found by (g)reedy search
  starting state: [t,1,2,5,10,12,15]-[]
  with a limit of 100 steps.
    steps            *states* 
---------------------------------------
    (15-0) -- [t,1,2,5,10,12,15]-[]
    (12-15) -- [2,5,10,12]-[t,1,15]
    (12-16) -- [t,1,2,5,10,12]-[15]
    (10-28) -- [2,5,10]-[t,1,12,15]
    (10-29) -- [t,1,2,5,10]-[12,15]
    (5-39) -- [2,5]-[t,1,10,12,15]
    (5-40) -- [t,1,2,5]-[10,12,15]
    (2-45) -- [2]-[t,1,5,10,12,15]
    (2-46) -- [t,1,2]-[5,10,12,15]
    (0-48) -- []-[t,1,2,5,10,12,15]

datime(2002,3,20,1,44,5) -- datime(2002,3,20,1,44,6)