import oeis

-- valid sequence
lookupSequence [1,1,2,3,5]

-- empty list
lookupSequence []

-- unknown sequence
lookupSequence [1,10011]

-- known sequence
extendSequence [1,3,5,7]

-- empty list
extendSequence []

-- unknown sequence
extendSequence [1,10011]

-- extend a long sequence
extendSequence [1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,83,85,87,89,91,93,95,97,99]