A258425 Total number of partitions of all hypercubes resulting from a sequence of n bisections, each of which splits any part perpendicular to any of the axes, such that each dimension is used at least once.
1, 1, 6, 64, 1020, 21854, 590248, 19268098, 738194780, 32481348812, 1614506203400, 89478362311442, 5471239864890436, 365900668319641264, 26569358218427144576, 2081825562568924254126, 175078869470374599592604, 15730138729512408087404292
Offset: 0
Keywords
Examples
a(2) = 2 + 4 = 6: In one dimension: [||-], [-||] . .___. .___. .___. .___. In two dimensions: |_| | | |_| |_|_| |___| . |_|_| |_|_| |___| |_|_| .
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..135
Crossrefs
Row sums of A255982.
Programs
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Maple
b:= proc(n, k, t) option remember; `if`(t=0, 1, `if`(t=1, A(n-1, k), add(A(j, k)*b(n-j-1, k, t-1), j=0..n-2))) end: A:= proc(n, k) option remember; `if`(n=0, 1, -add(binomial(k, j)*(-1)^j*b(n+1, k, 2^j), j=1..k)) end: T:= proc(n, k) option remember; add(A(n, k-i)*(-1)^i*binomial(k, i), i=0..k) end: a:= n-> add(T(n,k), k=0..n): seq(a(n), n=0..20);
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Mathematica
b[n_, k_, t_] := b[n, k, t] = If[t==0, 1, If[t==1, A[n-1, k], Sum[A[j, k]* b[n-j-1, k, t-1], {j, 0, n-2}]]]; A[n_, k_] := A[n, k] = If[n==0, 1, -Sum[Binomial[k, j]*(-1)^j*b[n+1, k, 2^j], {j, 1, k}]]; T[n_, k_] := T[n, k] = Sum[A[n, k-i]*(-1)^i*Binomial[k, i], {i, 0, k}]; a[n_] := Sum[T[n, k], {k, 0, n}]; Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Feb 07 2017, translated from Maple *)
Formula
a(n) = Sum_{k=0..n} A255982(n,k).
a(n) ~ 2^(2*n-5/8) * n^(n-1) / (exp(n) * (log(2))^(n+1)). - Vaclav Kotesovec, May 30 2015