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Examples of what not to submit

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Some real examples of sequences that were rejected

The following are real examples of submissions that were rejected:

  • A-numbers of sequences contributed by [your name] (however, this might be appropriate on your OEIS Wiki user page).
  • Experience points required for a Pokemon in the "erratic" experience group to be of level n.
  • The year 10^n decimal digits of pi were first computed (Not well-defined!)
  • Primes of the form n^3 + 2 n^2 + 37 n + 73.
  • Non-trivial circulation in decreasing order: numbers of the form lim_{x->+inf}(a[x]b) with b<>1.
  • You start at the number 1 and you add 2 until you get to the 4th number in the sequence, in which you then add the 1st and 3rd number of the sequence, which will give you 6. Then you do the same thing, adding 2 to each sequence, but for every 4th number you add the 1st and 3rd number before it.
  • Consecutive Quotients minus a third term x(k) = fix(a*x(k-1)/x(k-2))-b*x(k-3).
  • Prime numbers of the form 1 plus n x 10@r (@ means "to the power of") where n is an integer between 1 and 9 inclusive, and r is an integer greater than or equal to 0.
  • Concatenate a semiprime with a Fibonacci number to obtain a palindrome with at least two distinct digits.
  • The sequence 1,2,3 (and no further terms are known). The sequence 2,4,6 (and no further terms are known).

Other (somewhat exaggerated) examples of rejections

The following are only slightly exaggerated versions of earlier sequences that were rejected as inappropriate.

  • Numbers n such that d(n)+sigma(n)+phi(n)+prime(n) is a perfect cube.
  • Numbers n such that 7^n + 361*n - 5*sqrt(n) is a semiprime.
  • Successive primes encountered in decimal expansion of fifth root of 13.
  • The number of bars in Beethoven's nth symphony.
  • John Doe's sequence
  • Oblong wombat numbers
  • A vector matrix Markov based on the p-adic version of the Schopenhauerian group gamma matrix.
  • Quantum eigenvalues of Buckminster Fuller's epistemological pseudomorphism.
  • Number of children of n-th Speaker of the US House of Representatives on the day he was elected.
  • Time of sunset in Woodstock, NY, on n-th day of 2016, rounded to the nearest hour.
  • Number of letters in the n-th word defined in Webster's English Dictionary.
  • Length of line when n is printed using Helvetica Regular 12-point font, rounded to nearest millimeter.
  • The number of languages spoken in the states of India in 1900+n
  • The number of policemen killed in Chicago in the year 1900+n
  • The square kilometers encompassed by the boundary of the German Reich at dawn on February 1 1900+n.

Avoid short sequences and easily confused sequences

  • When the database was started, all sequences were supposed to be infinite (although there were soon many exceptions), and at least five terms were required.
  • Over the years these requirements have been relaxed, but it is good to keep them in mind.
  • Remember also that the primary purpose of the OEIS is to identify sequences.
  • So if you are thinking of submitting a new sequence, and all you know is that it begins 1,2,3,4, don't bother to submit it, it will not be accepted. There are already 9363 entries that match 1,2,3,4. Same thing for 1,3,5, or 2,3,5, or 2,6,8, etc.
  • Likewise for any short sequence: the more matches there are to it in the OEIS right now, the less chance there is that it will be accepted.
  • Remember too that our search mechanism deliberately ignores signs (although matches that have more sign agreements get ranked first) unless the "signed:" prefix is used. This means that if your sequence is just a string of +1's and -1's, it will match all the other sequences like that (there are over 500 of them). So unless yours is really really important, don't bother submitting it. (Instead, you might look at the indices where the -1's appear.)

See also