The information in this initial post is accurate as of January 2022.
EDIT by Sokwe: updated on 23 February 2023
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14 Bits
Currently, only two 14-cell objects are yet to appear naturally, both p2 oscillators:
- Melting clock: xp2_4l1148kgzx302
- Octapole: xp2_y1g0k053zg80a02z11
15 Bits
There are currently four still lifes which haven't had any natural occurrences: EDIT by Sokwe: now down to just one as of 23 February 2023
- Long^9 snake: xs15_y3g853zwg8421z65
- Nonapole: xp2_y2g0k053zw80a02z321
- Pseudo-barberpole: xp5_y2g0k413zwo0a02z32
16 Bits
I'm not sure as to what still lifes in specific are yet to appear naturally, however there are a total of 180 of them which have yet to appear (3106 have occurred naturally, of 3286 total).
EDIT by dvgrn: now down to 148 as of 10 June 2022
EDIT by Sokwe: now down to 94 as of 23 February 2023
As for oscillators, there are 18 period-2 oscillators of this size yet to be seen from soup:
EDIT by dvgrn: now down to 17 as of 30 June 2022
EDIT by Sokwe: now down to 12 as of 23 February 2023
- Decapole: xp2_y3g0k053zx80a02z6501
- Tripole tie long snake: xp2_xg8o64213zca02
- xp2_k3g44gljz11
- xp2_kg34azwa4o15
- xp2_8a2543gkz010602
- xp2_ia284gljz11
- xp2_4k4g4gljz32
- xp2_350k0l51z0642
- xp2_3lg42mzx10246
- xp2_062k0l51zca02
- xp2_350k04gj4zx642
- xp2_bh284gljz01
- Tripole tie snake: xp2_bdggzw1050ko (found 4 Apr. 2022 by Charity Engine)
- Phoenix with cavity: xp2_882030kgz014a86 (found 30 Jun. 2022 by Charity Engine)
- Bipole tie shillelagh tail: xp2_mp3zw31ago (found 13 Feb. 2022 by kaarel.toomet)
- Cis-long snake tie very long snake: xs15_3lozx31248c (found 13 Aug. 2022 by Charity Engine)
- xs15_321e88gzxca1 (found 21 Feb. 2023 by Charity Engine)
- xs15_o4a5123z056 (found 27 Aug. 2022 by Charity Engine)
- Cha cha: xp2_4o6o7o68zx1 (found 7 Jul. 2022 by Charity Engine; note that this was first discovered in a C2_2 soup that did not rely on symmetry to produce the oscillator, and the C1 occurrence is essentially a duplicate)
- Trans-bipole-tie: xp2_31agozy131ago (found 13 Dec. 2022 by Charity Engine)
- Tripole tie eater head: xp2_178cggzy01050ko (found 30 Oct. 2022 by Charity Engine)
- Boat tie pentapole: xp2_y1g0k053zg8o642z01 (found 19 Dec. 2022 by Charity Engine)
- xp2_0g4j04g53z32x3 (unknown discoverer and date; note that, like cha-cha, this did not occurr in the official C1 symmetry, but a C1 soup does exist for this pattern derived from a C2_2 soup that does not rely on symmetry to produce the oscillator)
