README

A selection of programs that relate to potential or actual sequences
in the OEIS (<http://www.oeis.org>).

k-steppable:
  How many of the b^n strings of length n, base b can be partitioned in at
  least one way into k non-empty substrings such that the substrings appear
  in lexical order?

A001055:
  Number of ways of factoring n with all factors >1, focusing on records.

jacobsthal:
  Given n, what is the longest possible sequence of consecutive integers
  each of which has a common factor with n? Perl and C code variants of
  the same algorithm.

divrep:
  Investigation of sequences involving arithmetic series related to tau(n),
  including A064491, A088430, A165497, A165498, A165499, A165500, A165501.
  **Note** now moved to its own repo, see https://github.com/hvds/divrep

zerofree:
  Given a calculation such as s->s^2, find the minimal set that includes 2
  and is fixed under the transformation: apply the calculation to each
  element, write the resulting value in some base <n>, split on any zero
  digits, and collate the resulting substrings as base <n> values.
  This gives A113917 and A113918.

A101877:
  Given n, find the least integer such that there is a sum of distinct unit
  fractions equal to n, the greatest denominator being a(n).

A249064:
  Find the lexically first sequence of positive integers such that each
  element a(n) is coprime to the next a(n) elements. Also find A090252,
  where each element a(n) is coprime to the next n elements.

least_eg:
  Find A097048(n) and A097049(n), the numerator and denominator of the
  simplest rationals that cannot be expressed as the sum of fewer than
  n unit fractions.

part:
  Count the partitions of a n-dimensional cube of side 2, with or without
  symmetries.

wilson:
  Explore rationals r that may be solutions to David Wilson's puzzle:
  starting at 1, add r and then repeatedly either add r or take the
  reciprocal, trying to get back to 1.