Odd-base slice grammar

Claims · 19 dated claims on Odd-base slice grammar, each with its tag and its witness; newest 2026-09-23.

19 claims
  • Verified The odd-base generalisation rests on a choice of solid: Cook's predicate "at most one coordinate in the middle third" and the bang dim 3, code 23 rule "at most one odd coordinate" agree at base = 3 (20 of 27) and nowhere else, at base = 5 filling 4^3 + 3 * 4^2 = 112 of 125 against 3^3 + 3 * 2 * 3^2 = 81 = 4k^3 - 3k^2 at k = 3, and there is no canonical base-5 Menger sponge. Witness: lab/py/odd-base-slice-grammar.
  • Verified In the comparison of the slice dimension against the dimension minus one, the dimension is the solid's own log(fill)/log(base) and never the ambient 3: at the ambient 3 the value 3 - 1 = 2 exceeds all four slice dimensions 1.8184, 1.6869, 1.8026, 1.7204 and the mod-4 split collapses. Witness: lab/py/odd-base-slice-grammar.
  • Verified The four printed dimensions are consistent with the four printed rules and this is not evidence for either: the dominant roots (9 + sqrt(33))/2 = 7.37228, (11 + sqrt(369))/2 = 15.1047, (42 + sqrt(612))/2 = 33.3693, (28 + sqrt(3556))/2 = 43.8161 give log(root)/log(base) of 1.8183, 1.6870, 1.8026, 1.7204 at base = 3, 5, 7, 9, while 4k^3 - 3k^2 at k = 2..5 gives 20, 81, 208, 425 and dimension minus one 1.7268, 1.7304, 1.7430, 1.7544; a rule and its own dimension cannot cross-check each other. Witness: lab/py/odd-base-slice-grammar.
  • Proved The middle diagonal layer sits at coordinate sum 3(base-1)/2, odd exactly when base = 3 mod 4 (3, 6, 9, 12 at base = 3, 5, 7, 9). Witness: lab/py/odd-base-slice-grammar.
  • Conjecture No definition of a "blow-up of 4" for the slice exists in this tree, so the phrase carries no claim.
  • Conjecture The two-tile grammar closes at ten odd bases with a 2 x 2 substitution matrix rational in base within each class of base mod 4.
  • Conjecture That parity forces structurally different cells into the middle layer in each residue class, which is the mechanism of the mod-4 split.
  • Conjecture The two-tile grammar's 2 x 2 substitution matrix, rational in base within each class of base mod 4, reproduces every census matrix at odd bases 3..21, ten bases. Witness: lab/py/odd-base-slice-grammar, spectra.md THE CLAIM.
  • Conjecture The middle diagonal layer sits at coordinate sum 3(base-1)/2, odd exactly when base = 3 mod 4, the candidate mechanism of the mod-4 split; the side test runs to odd base 401 and the mechanism itself has no generator. Witness: spectra.md OPEN QUESTIONS, lab/py/odd-base-slice-grammar for the side test.
  • Verified The carry automaton M[c, c'] = P_b[c + g - b c'] on abs(c) <= 1, g = 3(b-1)/2, P_b the digit polynomial of the solid with at most one odd coordinate, has even block [[M[0,0], M[0,1]], [M[1,0] + M[-1,0], M[1,1] + M[-1,1]]] equal to spectra's closed form at all twelve odd bases b = 3..25, [[6,1],[6,3]], [[7,3],[30,4]], [[30,3],[24,12]], [[19,9],[96,9]], [[72,6],[54,27]], [[37,18],[198,16]] and on; no carry leaves abs(c) <= 1, the pair ((M^n)[0,0], (M^n)[1,0] + (M^n)[-1,0]) obeys the block at levels 0..8, and a direct digit-sum census at heights h_n - 1, h_n, h_n + 1, h_n = 3(b^n - 1)/2, returns the same pairs at levels 0..6 at b = 3, 0..5 at b = 5, 0..4 at b = 7, 9 and 0..3 at b = 11..25. Witness: lab/py/spectra-from-cuts verb block.
  • Proved The correspondence between the two-tile census and the carry automaton is exact, with no index shift and no factor: the plane x + y + z = 3 b^n / 2 = h_n + 3/2 cuts the level-n cells of corner sum h_n - 1, h_n, h_n + 1 at offsets 5/2, 3/2, 1/2, so hexagons_n = (M^n)[0, 0] and triangles_n = (M^n)[1, 0] + (M^n)[-1, 0] with hexagons_0 = 1, and h_n = g(1 + b + .. + b^(n-1)) is the central height of cuts at dim = 3 with the target digit dim replaced by g = 3(b-1)/2, which is 3 again at b = 3. Witness: spectra.md THE COMPOSITION, lab/py/spectra-from-cuts verb block.
  • Proved At every odd base b, (hexagons, triangles)_(n+1) = S_b (hexagons, triangles)_n with S_b = [[P_b[g], P_b[g+b]], [2 P_b[g+1], P_b[g+b-1] + P_b[g+b+1]]], the even block of the carry automaton on (hexagons, triangles), the basis {e_0, (e_1 + e_(-1))/2}: the carry contracts because abs(c + g - s) <= g + 1 < 2b for abs(c) <= 1 and 0 <= s <= 2g, and d -> b - 1 - d keeps digit parity at odd b so P_b[s] = P_b[2g - s] and M[-c, -c'] = M[c, c'], whence M^n e_0 = hexagons_n e_0 + (triangles_n / 2)(e_1 + e_(-1)); S_3 = [[6,1],[6,3]] is Abel's matrix and its recurrence is the one cuts proves. Supersedes the Conjecture row of 2026-08-28 "The two-tile grammar closes at ten odd bases with a 2 x 2 substitution matrix rational in base within each class of base mod 4". Witness: spectra.md THE COMPOSITION, lab/py/spectra-from-cuts verb block.
  • Proved P_b(t) = E^2 (E + 3 O) with E = 1 + t^2 + .. + t^(b-1) and O = t + t^3 + .. + t^(b-2), E^3 carrying the even exponents and 3 O E^2 the odd ones, so with n = (b+1)/2 the five entries are binomial extractions from ((1 - x^n)/(1 - x))^3 and (1 - x^(n-1))(1 - x^n)^2/(1 - x)^3: when b = 3 mod 4, P_b[g] = 3(b+1)(3b-1)/16, P_b[g+1] = 3(b+1)^2/16, P_b[g+b] = (b+1)(b+5)/32, P_b[g+b-1] = 3(b+1)(b+5)/32, P_b[g+b+1] = 3(b-3)(b+1)/32; when b = 1 mod 4, P_b[g] = (3b^2+6b+7)/16, P_b[g+1] = 3(b-1)(3b+5)/16, P_b[g+b] = 3(b-1)(b+3)/32, P_b[g+b-1] = (b+3)(b+7)/32, P_b[g+b+1] = (b-1)(b+3)/32; the active binomials are stable from b >= 11 at the latest and every form matches the digit polynomial at odd b = 3..101. Witness: lab/py/spectra-from-cuts verb forms.
  • Proved The closed forms of spectra's THE CLAIM hold at every odd base, by substitution of the five coefficients into S_b: trace 3b(b+1)/4 and determinant 3(b-1)(b+1)^3/32 when b = 3 mod 4, trace (b^2+3b+4)/4 and determinant -(b+3)(3b^3-3b^2-11b+3)/32 when b = 1 mod 4; the mod-4 split of the matrix is the parity of g = 3(b-1)/2, odd exactly when b = 3 mod 4, which reads P_b[g], P_b[g+b-1], P_b[g+b+1] from 3 O E^2 and P_b[g+1], P_b[g+b] from E^3 in that class, all five swapping parts in the other. Supersedes the Conjecture row of 2026-09-21 "The two-tile grammar's 2 x 2 substitution matrix, rational in base within each class of base mod 4, reproduces every census matrix at odd bases 3..21, ten bases" and the Conjecture row of 2026-08-28 "That parity forces structurally different cells into the middle layer in each residue class, which is the mechanism of the mod-4 split". Witness: spectra.md THE COMPOSITION, lab/py/spectra-from-cuts verb forms.
  • Proved The mod-4 side at every odd base: with q = fill/b = n^2(4n-3)/(2n-1) and chi the characteristic polynomial of S_b, (2n-1)(trace - 2q) reads -n(4n^2-3)/2 and -(n-1)(12n^2-1)/2, both negative, and (2n-1)^2 chi(q) reads -n^3(4n^3 - 12n^2 + 15n - 6)/2 < 0 for even n >= 2 and (n-1)^2(4n^4 - 4n^3 + 7n^2 - 1)/2 > 0 for odd n >= 3, every real root of every factor below the first n of its class, so rho_b > fill/b when b = 3 mod 4 and rho_b < fill/b when b = 1 mod 4, the box-counting exponent log_b(rho_b) above or below log_b(fill) - 1 accordingly. Supersedes the Conjecture row of 2026-09-21 "The middle diagonal layer sits at coordinate sum 3(base-1)/2, odd exactly when base = 3 mod 4, the candidate mechanism of the mod-4 split; the side test runs to odd base 401 and the mechanism itself has no generator". Witness: lab/py/spectra-from-cuts verb split, roots isolated exactly.
  • Proved P_b(w) = -2/(1+w)^3 at every b-th root of unity w != 1, since E(w) = 1/(1+w) and O(w) = -1/(1+w) there, P_b(w)(1+w)^3 + 2 being divisible by 1 + w + .. + w^(b-1); the residue-class sums of P_b modulo b are the row sums of the automaton, the class of g summing to (b+1)(5b+1)/8 or (3b^2+6b-1)/8 and each class of g +- 1 to 3(b+1)^2/8 or (5b^2+6b-3)/8 by class 3, 1 mod 4; the block is five single coefficients and not class sums. Witness: lab/py/spectra-from-cuts verb classes, odd b = 3..25 for the divisibility and 3..101 for the sums.
  • Verified At base 5 the substitution read off polygons cut from cells is H -> 7 H + 15 T+ + 15 T-, T+ -> 3 H + 3 T+ + 1 T-, T- -> 3 H + 1 T+ + 3 T-, folded to [[7,3],[30,4]], the T- pattern the half-turn of the T+ pattern, every child polygon inside its parent, census (7, 30), (139, 330), (1963, 5490) at levels 1..3; at base 3, levels 1..4, Abel's rule and (6, 6), (42, 54), (306, 414), (2250, 3078). Witness: lab/py/spectra-from-cuts verb tiles.
  • Proved At every odd base b the centroid diagonal slice of the solid whose base-b digit triples have at most one odd coordinate is the attractor of a graph-directed system of ratio-1/b homotheties on three tiles T+, H, T-, the cuts of cells at doubled offset 1, 3, 5, with incidence the carry automaton M[c, c'] = P_b[c + g - b c'], the open set condition from the disjoint open cells, and two prototiles up to the half-turn d -> b - 1 - d, a regular hexagon and an equilateral triangle. Witness: spectra.md THE COMPOSITION, The tiles.
  • Proved The Hausdorff and box-counting dimensions of that slice are both log_b(rho_b), rho_b the dominant root of S_b, by the cover of level-n tiles and the mass distribution principle on the left Perron vector of M, a disc of radius b^-n meeting at most 64 level-n cells. Witness: spectra.md THE COMPOSITION, The tiles.