We compute the equation and nonminimal resolution F of the carpet of type (a,b) where $a \ge b$ over a larger finite prime field, lift the complex to the integers, which is possible since the coefficients are small. Finally we study the nonminimal strands over ZZ by computing the Smith normal form. The resulting data allow us to compute the Betti tables for arbitrary primes.
i1 : a=5,b=5 o1 = (5, 5) o1 : Sequence |
i2 : h=carpetBettiTables(a,b) -- 0.00207907 seconds elapsed -- 0.0195683 seconds elapsed -- 0.0264118 seconds elapsed -- 0.0109624 seconds elapsed -- 0.00333593 seconds elapsed 0 1 2 3 4 5 6 7 8 9 o2 = HashTable{0 => total: 1 36 160 315 288 288 315 160 36 1} 0: 1 . . . . . . . . . 1: . 36 160 315 288 . . . . . 2: . . . . . 288 315 160 36 . 3: . . . . . . . . . 1 0 1 2 3 4 5 6 7 8 9 2 => total: 1 36 167 370 476 476 370 167 36 1 0: 1 . . . . . . . . . 1: . 36 160 322 336 140 48 7 . . 2: . . 7 48 140 336 322 160 36 . 3: . . . . . . . . . 1 0 1 2 3 4 5 6 7 8 9 3 => total: 1 36 160 315 302 302 315 160 36 1 0: 1 . . . . . . . . . 1: . 36 160 315 288 14 . . . . 2: . . . . 14 288 315 160 36 . 3: . . . . . . . . . 1 o2 : HashTable |
i3 : T= carpetBettiTable(h,3) 0 1 2 3 4 5 6 7 8 9 o3 = total: 1 36 160 315 302 302 315 160 36 1 0: 1 . . . . . . . . . 1: . 36 160 315 288 14 . . . . 2: . . . . 14 288 315 160 36 . 3: . . . . . . . . . 1 o3 : BettiTally |
i4 : J=canonicalCarpet(a+b+1,b,Characteristic=>3); ZZ o4 : Ideal of --[x ..x , y ..y ] 3 0 5 0 5 |
i5 : elapsedTime T'=minimalBetti J -- 0.303464 seconds elapsed 0 1 2 3 4 5 6 7 8 9 o5 = total: 1 36 160 315 302 302 315 160 36 1 0: 1 . . . . . . . . . 1: . 36 160 315 288 14 . . . . 2: . . . . 14 288 315 160 36 . 3: . . . . . . . . . 1 o5 : BettiTally |
i6 : T-T' 0 1 2 3 4 5 6 7 8 9 o6 = total: . . . . . . . . . . 1: . . . . . . . . . . 2: . . . . . . . . . . 3: . . . . . . . . . . o6 : BettiTally |
i7 : elapsedTime h=carpetBettiTables(6,6); -- 0.0038861 seconds elapsed -- 0.0195659 seconds elapsed -- 0.162311 seconds elapsed -- 1.61661 seconds elapsed -- 0.515774 seconds elapsed -- 0.0428007 seconds elapsed -- 0.00616336 seconds elapsed -- 5.66946 seconds elapsed |
i8 : keys h o8 = {0, 2, 3, 5} o8 : List |
i9 : carpetBettiTable(h,7) 0 1 2 3 4 5 6 7 8 9 10 11 o9 = total: 1 55 320 891 1408 1155 1155 1408 891 320 55 1 0: 1 . . . . . . . . . . . 1: . 55 320 891 1408 1155 . . . . . . 2: . . . . . . 1155 1408 891 320 55 . 3: . . . . . . . . . . . 1 o9 : BettiTally |
i10 : carpetBettiTable(h,5) 0 1 2 3 4 5 6 7 8 9 10 11 o10 = total: 1 55 320 891 1408 1275 1275 1408 891 320 55 1 0: 1 . . . . . . . . . . . 1: . 55 320 891 1408 1155 120 . . . . . 2: . . . . . 120 1155 1408 891 320 55 . 3: . . . . . . . . . . . 1 o10 : BettiTally |
The object carpetBettiTables is a method function.