Voozh

A329982

a(1) = 0, and for n > 0, a(n+1) = k^2 - a(n) where k is the number of terms equal to a(n) among the first n terms.

0, 1, 0, 4, -3, 4, 0, 9, -8, 9, -5, 6, -5, 9, 0, 16, -15, 16, -12, 13, -12, 16, -7, 8, -7, 11, -10, 11, -7, 16, 0, 25, -24, 25, -21, 22, -21, 25, -16, 17, -16, 20, -19, 20, -16, 25, -9, 10, -9, 13, -9, 18, -17, 18, -14, 15, -14, 18, -9, 25, 0, 36, -35, 36, -32

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OFFSET

1,4

COMMENTS

In other words, for n > 0, a(n+1) = o(n)^2 - a(n) where o is the ordinal transform of the sequence.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, Scatterplot of the first 2^20 terms

EXAMPLE

The first terms, alongside their ordinal transform, are:

n a(n) o(n)

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