A363086 a(0)=a(1)=1. For n>1, let c=count of all occurrences of a(n-1) in the list so far. If c < abs(a(n-1)), then a(n)=c-a(n-1). Otherwise, a(n)=c.

1, 1, 2, -1, 1, 3, -2, 3, -1, 2, 2, 3, 3, 4, -3, 4, -2, 2, 4, -1, 3, 5, -4, 5, -3, 5, -2, 3, 6, -5, 6, -4, 6, -3, 3, 7, -6, 7, -5, 7, -4, 7, -3, 4, 4, 5, -1, 4, 6, -2, 4, 7, -2, 5, 5, 6, -1, 5, 7, -1, 6, 6, 7, 7, 8, -7, 8, -6, 8, -5, 8, -4, 4, 8, -3, 5, 8, -2

Offset

0,3

Comments

This is a variant of A363083.

Links

Gavin Lupo, Table of n, a(n) for n = 0..50000

Gavin Lupo, Image of the first 1000000 terms

Example

a(0) =  1
a(1) =  1
a(2) =  2. Two 1's in the list so far.  2 > abs(1).      c =  2.
a(3) = -1. One 2 in the list so far.    1 < abs(2).  1 - 2 = -1.
a(4) =  1. One -1 in the list so far.   1 = abs(-1).     c =  1.

Prog

(Python)
from itertools import islice
from collections import Counter
def agen(): # generator of terms
    an, c = 1, Counter([1, 1])
    yield from [1, 1]
    while True:
        an = c[an]-an if c[an] < abs(an) else c[an]
        c[an] += 1
        yield an
print(list(islice(agen(), 80))) # Michael S. Branicky, May 19 2023

Crossrefs

Cf. A363083.

Sequence in context: A117506 A179205 A055089 * A060117 A196526 A234504

Adjacent sequences: A363083 A363084 A363085 * A363087 A363088 A363089

Keyword

sign,easy,look

Author

Gavin Lupo, May 18 2023

Status

approved