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THE VAN DER CORPUT SEQUENCE

''See main article Van Der Corput Sequence ''

Let

:
n=\sum_{k=0}^{L-1}d_k(n)b^k


be the ''b''-ary representation of the positive integer ''n'' ≥ 1, i.e. 0 ≤ ''d''k(''n'') < ''b''. Set

:
g_b(n)=\sum_{k=0}^{L-1}d_k(n)b^{-k-1}.


Then there is a constant ''C'' depending only on ''b'' such that (''g''''b''(''n''))''n'' ≥ 1 satisfies

:
  • _N(g_b(1),\dots,g_b(N))\leq C rac{\log N}{N}.




THE HALTON SEQUENCE

''See main article Halton Sequences ''

The Halton sequence is a natural generalization of the van der Corput sequence to higher dimensions. Let ''s'' be an arbitrary dimension and ''b''1, ..., ''b''''s'' be arbitrary Coprime integers greater than 1. Define

:
x(n)=(g_{b_1}(n),\dots,g_{b_s}(n)).


Then there is a constant ''C'' depending only on ''b''1, ..., ''b''''s'', such that (''x''(''n''))''n''≥1 is a ''s''-dimensional sequence with

:
  • _N(x(1),\dots,x(N))\leq C' rac{(\log N)^s}{N}.




THE HAMMERSLEY SET


Let ''b''1,...,''b''s-1 be Coprime positive integers greater that 1. For given ''s'' and ''N'', the ''s''-dimensional Hammersley set of size ''N'' is defined by

:
x(n)=(g_{b_1}(n),\dots,g_{b_{s-1}}(n), rac{n}{N})


for ''n'' = 1, ..., ''N''. Then

:
  • _N(x(1),\dots,x(N))\leq C rac{(\log N)^{s-1}}{N}



where ''C'' is a constant depending only on ''b''1, ..., ''b''''s''−1.