id sid tid token lemma pos jd472v26441 1 1 given give VERB jd472v26441 1 2 two two NUM jd472v26441 1 3 graphs graph NOUN jd472v26441 1 4 g g PROPN jd472v26441 1 5 and and CCONJ jd472v26441 1 6 h h NOUN jd472v26441 1 7 , , PUNCT jd472v26441 1 8 a a DET jd472v26441 1 9 homomorphism homomorphism NOUN jd472v26441 1 10 from from ADP jd472v26441 1 11 g g PROPN jd472v26441 1 12 to to ADP jd472v26441 1 13 h h PROPN jd472v26441 1 14 is be AUX jd472v26441 1 15 a a DET jd472v26441 1 16 map map NOUN jd472v26441 1 17 from from ADP jd472v26441 1 18 the the DET jd472v26441 1 19 vertices vertex NOUN jd472v26441 1 20 of of ADP jd472v26441 1 21 g g NOUN jd472v26441 1 22 to to ADP jd472v26441 1 23 the the DET jd472v26441 1 24 vertices vertex NOUN jd472v26441 1 25 of of ADP jd472v26441 1 26 h h NOUN jd472v26441 1 27 that that PRON jd472v26441 1 28 preserves preserve VERB jd472v26441 1 29 adjacency adjacency NOUN jd472v26441 1 30 . . PUNCT jd472v26441 2 1 many many ADJ jd472v26441 2 2 graph graph NOUN jd472v26441 2 3 notions notion NOUN jd472v26441 2 4 can can AUX jd472v26441 2 5 be be AUX jd472v26441 2 6 described describe VERB jd472v26441 2 7 using use VERB jd472v26441 2 8 graph graph NOUN jd472v26441 2 9 homomorphisms homomorphism NOUN jd472v26441 2 10 , , PUNCT jd472v26441 2 11 including include VERB jd472v26441 2 12 independent independent ADJ jd472v26441 2 13 sets set NOUN jd472v26441 2 14 , , PUNCT jd472v26441 2 15 matchings matching NOUN jd472v26441 2 16 , , PUNCT jd472v26441 2 17 and and CCONJ jd472v26441 2 18 graph graph NOUN jd472v26441 2 19 colorings coloring NOUN jd472v26441 2 20 . . PUNCT jd472v26441 3 1 in in ADP jd472v26441 3 2 this this DET jd472v26441 3 3 dissertation dissertation NOUN jd472v26441 3 4 , , PUNCT jd472v26441 3 5 we we PRON jd472v26441 3 6 consider consider VERB jd472v26441 3 7 questions question NOUN jd472v26441 3 8 in in ADP jd472v26441 3 9 each each PRON jd472v26441 3 10 of of ADP jd472v26441 3 11 these these DET jd472v26441 3 12 areas area NOUN jd472v26441 3 13 . . PUNCT jd472v26441 4 1 wang wang PROPN jd472v26441 4 2 and and CCONJ jd472v26441 4 3 zhu zhu PROPN jd472v26441 4 4 [ [ PUNCT jd472v26441 4 5 49 49 NUM jd472v26441 4 6 ] ] PUNCT jd472v26441 4 7 demonstrated demonstrate VERB jd472v26441 4 8 the the DET jd472v26441 4 9 log log NOUN jd472v26441 4 10 - - PUNCT jd472v26441 4 11 concavity concavity NOUN jd472v26441 4 12 of of ADP jd472v26441 4 13 the the DET jd472v26441 4 14 independence independence NOUN jd472v26441 4 15 polynomial polynomial ADJ jd472v26441 4 16 for for ADP jd472v26441 4 17 a a DET jd472v26441 4 18 number number NOUN jd472v26441 4 19 of of ADP jd472v26441 4 20 infinite infinite ADJ jd472v26441 4 21 recursively recursively ADV jd472v26441 4 22 - - PUNCT jd472v26441 4 23 defined define VERB jd472v26441 4 24 graph graph NOUN jd472v26441 4 25 classes class NOUN jd472v26441 4 26 . . PUNCT jd472v26441 5 1 for for ADP jd472v26441 5 2 the the DET jd472v26441 5 3 first first ADJ jd472v26441 5 4 question question NOUN jd472v26441 5 5 that that PRON jd472v26441 5 6 we we PRON jd472v26441 5 7 consider consider VERB jd472v26441 5 8 , , PUNCT jd472v26441 5 9 we we PRON jd472v26441 5 10 extend extend VERB jd472v26441 5 11 their their PRON jd472v26441 5 12 method method NOUN jd472v26441 5 13 to to PART jd472v26441 5 14 demonstrate demonstrate VERB jd472v26441 5 15 the the DET jd472v26441 5 16 log log NOUN jd472v26441 5 17 - - PUNCT jd472v26441 5 18 concavity concavity NOUN jd472v26441 5 19 of of ADP jd472v26441 5 20 the the DET jd472v26441 5 21 independence independence NOUN jd472v26441 5 22 polynomial polynomial ADJ jd472v26441 5 23 for for ADP jd472v26441 5 24 a a DET jd472v26441 5 25 wider wide ADJ jd472v26441 5 26 range range NOUN jd472v26441 5 27 of of ADP jd472v26441 5 28 such such ADJ jd472v26441 5 29 classes class NOUN jd472v26441 5 30 , , PUNCT jd472v26441 5 31 showing show VERB jd472v26441 5 32 , , PUNCT jd472v26441 5 33 for for ADP jd472v26441 5 34 example example NOUN jd472v26441 5 35 , , PUNCT jd472v26441 5 36 that that SCONJ jd472v26441 5 37 the the DET jd472v26441 5 38 ( ( PUNCT jd472v26441 5 39 n,2)-centipede n,2)-centipede NOUN jd472v26441 5 40 and and CCONJ jd472v26441 5 41 ( ( PUNCT jd472v26441 5 42 n,2,k)-star n,2,k)-star PROPN jd472v26441 5 43 - - PUNCT jd472v26441 5 44 centipede centipede NOUN jd472v26441 5 45 have have VERB jd472v26441 5 46 log log NOUN jd472v26441 5 47 - - PUNCT jd472v26441 5 48 concave concave NOUN jd472v26441 5 49 independence independence NOUN jd472v26441 5 50 polynomials polynomial NOUN jd472v26441 5 51 for for ADP jd472v26441 5 52 even even ADV jd472v26441 5 53 n n NOUN jd472v26441 5 54 and and CCONJ jd472v26441 5 55 all all DET jd472v26441 5 56 k k NOUN jd472v26441 5 57 , , PUNCT jd472v26441 5 58 and and CCONJ jd472v26441 5 59 we we PRON jd472v26441 5 60 describe describe VERB jd472v26441 5 61 a a DET jd472v26441 5 62 technique technique NOUN jd472v26441 5 63 that that PRON jd472v26441 5 64 can can AUX jd472v26441 5 65 be be AUX jd472v26441 5 66 applied apply VERB jd472v26441 5 67 in in ADP jd472v26441 5 68 the the DET jd472v26441 5 69 pursuit pursuit NOUN jd472v26441 5 70 of of ADP jd472v26441 5 71 results result NOUN jd472v26441 5 72 for for ADP jd472v26441 5 73 other other ADJ jd472v26441 5 74 similarly similarly ADV jd472v26441 5 75 - - PUNCT jd472v26441 5 76 structured structure VERB jd472v26441 5 77 graphs graph NOUN jd472v26441 5 78 . . PUNCT jd472v26441 6 1 the the DET jd472v26441 6 2 graphs graph NOUN jd472v26441 6 3 in in ADP jd472v26441 6 4 question question NOUN jd472v26441 6 5 give give VERB jd472v26441 6 6 rise rise NOUN jd472v26441 6 7 to to ADP jd472v26441 6 8 k k X jd472v26441 6 9 - - ADJ jd472v26441 6 10 periodic periodic ADJ jd472v26441 6 11 recurrence recurrence NOUN jd472v26441 6 12 relations relation NOUN jd472v26441 6 13 . . PUNCT jd472v26441 7 1 we we PRON jd472v26441 7 2 present present VERB jd472v26441 7 3 a a DET jd472v26441 7 4 system system NOUN jd472v26441 7 5 for for ADP jd472v26441 7 6 reducing reduce VERB jd472v26441 7 7 these these DET jd472v26441 7 8 periodic periodic ADJ jd472v26441 7 9 recurrence recurrence NOUN jd472v26441 7 10 relations relation NOUN jd472v26441 7 11 to to ADP jd472v26441 7 12 ordinary ordinary ADJ jd472v26441 7 13 second second ADJ jd472v26441 7 14 - - PUNCT jd472v26441 7 15 order order NOUN jd472v26441 7 16 recurrence recurrence NOUN jd472v26441 7 17 relations relation NOUN jd472v26441 7 18 that that PRON jd472v26441 7 19 is be AUX jd472v26441 7 20 more more ADV jd472v26441 7 21 applicable applicable ADJ jd472v26441 7 22 than than ADP jd472v26441 7 23 existing exist VERB jd472v26441 7 24 work work NOUN jd472v26441 7 25 in in ADP jd472v26441 7 26 the the DET jd472v26441 7 27 field field NOUN jd472v26441 7 28 . . PUNCT jd472v26441 8 1 there there PRON jd472v26441 8 2 has have AUX jd472v26441 8 3 been be AUX jd472v26441 8 4 much much ADJ jd472v26441 8 5 discussion discussion NOUN jd472v26441 8 6 ( ( PUNCT jd472v26441 8 7 for for ADP jd472v26441 8 8 example example NOUN jd472v26441 8 9 , , PUNCT jd472v26441 8 10 [ [ PUNCT jd472v26441 8 11 52 52 NUM jd472v26441 8 12 ] ] PUNCT jd472v26441 8 13 , , PUNCT jd472v26441 8 14 [ [ X jd472v26441 8 15 26 26 NUM jd472v26441 8 16 ] ] PUNCT jd472v26441 8 17 , , PUNCT jd472v26441 8 18 and and CCONJ jd472v26441 8 19 [ [ X jd472v26441 8 20 22 22 NUM jd472v26441 8 21 ] ] PUNCT jd472v26441 8 22 ) ) PUNCT jd472v26441 8 23 , , PUNCT jd472v26441 8 24 on on ADP jd472v26441 8 25 the the DET jd472v26441 8 26 following following ADJ jd472v26441 8 27 question question NOUN jd472v26441 8 28 : : PUNCT jd472v26441 8 29 for for ADP jd472v26441 8 30 each each DET jd472v26441 8 31 fixed fix VERB jd472v26441 8 32 h h NOUN jd472v26441 8 33 , , PUNCT jd472v26441 8 34 n n NOUN jd472v26441 8 35 and and CCONJ jd472v26441 8 36 d d PROPN jd472v26441 8 37 , , PUNCT jd472v26441 8 38 what what PRON jd472v26441 8 39 is be AUX jd472v26441 8 40 the the DET jd472v26441 8 41 maximum maximum ADJ jd472v26441 8 42 , , PUNCT jd472v26441 8 43 over over ADP jd472v26441 8 44 all all DET jd472v26441 8 45 n n NOUN jd472v26441 8 46 - - PUNCT jd472v26441 8 47 vertex vertex NOUN jd472v26441 8 48 , , PUNCT jd472v26441 8 49 d d VERB jd472v26441 8 50 - - NOUN jd472v26441 8 51 regular regular ADJ jd472v26441 8 52 g g NOUN jd472v26441 8 53 , , PUNCT jd472v26441 8 54 of of ADP jd472v26441 8 55 hom(g hom(g PROPN jd472v26441 8 56 , , PUNCT jd472v26441 8 57 h h PROPN jd472v26441 8 58 ) ) PUNCT jd472v26441 8 59 , , PUNCT jd472v26441 8 60 the the DET jd472v26441 8 61 number number NOUN jd472v26441 8 62 of of ADP jd472v26441 8 63 homomorphisms homomorphism NOUN jd472v26441 8 64 from from ADP jd472v26441 8 65 g g PROPN jd472v26441 8 66 to to ADP jd472v26441 8 67 h h PROPN jd472v26441 8 68 ? ? PUNCT jd472v26441 9 1 while while SCONJ jd472v26441 9 2 the the DET jd472v26441 9 3 question question NOUN jd472v26441 9 4 has have AUX jd472v26441 9 5 been be AUX jd472v26441 9 6 largely largely ADV jd472v26441 9 7 settled settle VERB jd472v26441 9 8 for for ADP jd472v26441 9 9 bipartite bipartite PROPN jd472v26441 9 10 g g PROPN jd472v26441 9 11 , , PUNCT jd472v26441 9 12 it it PRON jd472v26441 9 13 is be AUX jd472v26441 9 14 still still ADV jd472v26441 9 15 quite quite ADV jd472v26441 9 16 open open ADJ jd472v26441 9 17 for for ADP jd472v26441 9 18 non non ADJ jd472v26441 9 19 - - ADJ jd472v26441 9 20 bipartite bipartite ADJ jd472v26441 9 21 g. g. PROPN jd472v26441 9 22 offering offer VERB jd472v26441 9 23 further further ADJ jd472v26441 9 24 progress progress NOUN jd472v26441 9 25 on on ADP jd472v26441 9 26 this this DET jd472v26441 9 27 question question NOUN jd472v26441 9 28 , , PUNCT jd472v26441 9 29 we we PRON jd472v26441 9 30 next next ADV jd472v26441 9 31 establish establish VERB jd472v26441 9 32 conditions condition NOUN jd472v26441 9 33 on on ADP jd472v26441 9 34 h h PROPN jd472v26441 9 35 , , PUNCT jd472v26441 9 36 in in ADP jd472v26441 9 37 terms term NOUN jd472v26441 9 38 of of ADP jd472v26441 9 39 certain certain ADJ jd472v26441 9 40 linear linear NOUN jd472v26441 9 41 programming programming NOUN jd472v26441 9 42 problems problem NOUN jd472v26441 9 43 , , PUNCT jd472v26441 9 44 under under ADP jd472v26441 9 45 which which PRON jd472v26441 9 46 we we PRON jd472v26441 9 47 can can AUX jd472v26441 9 48 obtain obtain VERB jd472v26441 9 49 an an DET jd472v26441 9 50 upper upper ADJ jd472v26441 9 51 bound bind VERB jd472v26441 9 52 on on ADP jd472v26441 9 53 hom(g;h hom(g;h NUM jd472v26441 9 54 ) ) PUNCT jd472v26441 9 55 , , PUNCT jd472v26441 9 56 valid valid ADJ jd472v26441 9 57 for for ADP jd472v26441 9 58 all all PRON jd472v26441 9 59 regular regular ADJ jd472v26441 9 60 g g NOUN jd472v26441 9 61 , , PUNCT jd472v26441 9 62 that that PRON jd472v26441 9 63 is be AUX jd472v26441 9 64 very very ADV jd472v26441 9 65 close close ADJ jd472v26441 9 66 to to ADP jd472v26441 9 67 best well ADV jd472v26441 9 68 possible possible ADJ jd472v26441 9 69 . . PUNCT jd472v26441 10 1 we we PRON jd472v26441 10 2 then then ADV jd472v26441 10 3 establish establish VERB jd472v26441 10 4 a a DET jd472v26441 10 5 number number NOUN jd472v26441 10 6 of of ADP jd472v26441 10 7 infinite infinite ADJ jd472v26441 10 8 families family NOUN jd472v26441 10 9 of of ADP jd472v26441 10 10 graphs graph NOUN jd472v26441 10 11 that that PRON jd472v26441 10 12 satisfy satisfy VERB jd472v26441 10 13 these these DET jd472v26441 10 14 conditions condition NOUN jd472v26441 10 15 . . PUNCT jd472v26441 11 1 finally finally ADV jd472v26441 11 2 , , PUNCT jd472v26441 11 3 we we PRON jd472v26441 11 4 present present VERB jd472v26441 11 5 a a DET jd472v26441 11 6 q q ADJ jd472v26441 11 7 - - ADJ jd472v26441 11 8 weighted weighted ADJ jd472v26441 11 9 enumeration enumeration NOUN jd472v26441 11 10 of of ADP jd472v26441 11 11 matchings matching NOUN jd472v26441 11 12 of of ADP jd472v26441 11 13 complete complete ADJ jd472v26441 11 14 bipartite bipartite ADJ jd472v26441 11 15 graphs graph NOUN jd472v26441 11 16 , , PUNCT jd472v26441 11 17 an an DET jd472v26441 11 18 enumeration enumeration NOUN jd472v26441 11 19 which which PRON jd472v26441 11 20 was be AUX jd472v26441 11 21 key key ADJ jd472v26441 11 22 to to ADP jd472v26441 11 23 proving prove VERB jd472v26441 11 24 the the DET jd472v26441 11 25 validity validity NOUN jd472v26441 11 26 of of ADP jd472v26441 11 27 a a DET jd472v26441 11 28 new new ADJ jd472v26441 11 29 combinatorial combinatorial ADJ jd472v26441 11 30 interpretation interpretation NOUN jd472v26441 11 31 of of ADP jd472v26441 11 32 the the DET jd472v26441 11 33 q q NOUN jd472v26441 11 34 - - NOUN jd472v26441 11 35 analog analog NOUN jd472v26441 11 36 of of ADP jd472v26441 11 37 a a DET jd472v26441 11 38 generalization generalization NOUN jd472v26441 11 39 of of ADP jd472v26441 11 40 the the DET jd472v26441 11 41 stirling stirling NOUN jd472v26441 11 42 numbers number NOUN jd472v26441 11 43 of of ADP jd472v26441 11 44 the the DET jd472v26441 11 45 second second ADJ jd472v26441 11 46 kind kind NOUN jd472v26441 11 47 in in ADP jd472v26441 11 48 work work NOUN jd472v26441 11 49 with with ADP jd472v26441 11 50 engbers engber NOUN jd472v26441 11 51 and and CCONJ jd472v26441 11 52 galvin galvin NOUN jd472v26441 11 53 [ [ X jd472v26441 11 54 20 20 NUM jd472v26441 11 55 ] ] PUNCT jd472v26441 11 56 . . PUNCT