Redone Japan house of representatives seats

[President Punxsutawney Phil]

OMOV setup for the House of Councilors

Aichi 7,484,094 (14) 7 in 2013 7 in 2016
Akita 1,022,839 (2) 1 in 2013 1 in 2016
Aomori 1,308,649 (2) 1 in 2013 1 in 2016
Chiba 6,224,027 (12) 6 in 2013 6 in 2016
Ehime 1,385,840 (3) 1 in 2013 2 in 2016
Fukui 787,099 (1) 1 in 2013
Fukuoka 5,102,871 (10) 5 in 2013 5 in 2016
Fukushima 1,913,606 (4) 2 in 2013 2 in 2016
Gifu 2,032,533 (4) 2 in 2013 2 in 2016
Gunma 1,973,476 (4) 2 in 2013 2 in 2016
Hiroshima 2,844,963 (5) 3 in 2013 2 in 2016
Hokkaido 5,383,579 (10) 5 in 2013 5 in 2016
Hyogo 5,536,989 (11) 6 in 2013 5 in 2016
Ibaraki 2,917,857 (6) 3 in 2013 3 in 2016
Ishikawa 1,154,343 (2) 1 in 2013 1 in 2016
Iwate 1,279,814 (2) 1 in 2013 1 in 2016
Kagawa 976,756 (2) 1 in 2013 1 in 2016
Kagoshima 1,648,752 (3) 1 in 2013 2 in 2016
Kanagawa 9,127,323 (17) 9 in 2013 8 in 2016
Kochi 728,461 (1) 1 in 2016
Kumamoto 1,786,969 (3) 2 in 2013 1 in 2016
Kyoto 2,610,140 (5) 2 in 2013 3 in 2016
Mie 1,815,827 (3) 2 in 2013 1 in 2016
Miyagi 2,334,215 (4) 2 in 2013 2 in 2016
Miyazaki 1,104,377 (2) 1 in 2013 2 in 2016
Nagano 2,099,759 (4) 2 in 2013 2 in 2016
Nagasaki 1,377,780 (3) 2 in 2013 1 in 2016
Nara 1,365,008 (3) 1 in 2013 2 in 2016
Niigata 2,305,098 (4) 2 in 2013 2 in 2016
Oita 1,166,729 (2) 1 in 2013 1 in 2016
Okayama 1,922,181 (4) 2 in 2013 2 in 2016
Okinawa 1,434,138 (3) 1 in 2013 2 in 2016
Osaka 8,838,908 (17) 9 in 2013 8 in 2016
Saga 833,245 (2) 1 in 2013 1 in 2016
Saitama 7,261,271 (14) 7 in 2013 7 in 2016
Shiga 1,413,184 (3) 1 in 2013 2 in 2016
Shimane 694,188 (1) 1 in 2013
Shizuoka 3,701,181 (7) 3 in 2013 2 in 2016
Tochigi 1,974,671 (4) 2 in 2013 2 in 2016
Tokushima 756,063 (1) 1 in 2016
Tokyo 13,513,734 (26) 13 in 2013 13 in 2016
Tottori 573,648 (1) 1 in 2013
Toyama 1,066,883 (2) 1 in 2013 1 in 2016
Wakayama 963,850 (2) 1 in 2013 1 in 2016
Yamagata 1,122,957 (2) 1 in 2013 1 in 2016
Yamaguchi 1,405,007 (3) 1 in 2013 2 in 2016
Yamanashi 835,165 (2) 1 in 2013 1 in 2016
total: 127,110,047
525,248 per member, if 242 members

[President Punxsutawney Phil]

[President Punxsutawney Phil]

under Adams and Webster methods:
two districts are nested in Setagaya
one district is nested in Shinagawa
meguro and ota can nest 2
minato, chiyoda, and chuo can nest 1
shinjuku, shibuya, and nakano can nest 2
suginami and nerima can nest 3
bunkyo and taito can nest 1
toshima and itabashi can nest 2
kita, arakawa, and adachi can nest 3
edogawa and sumida can nest 2
and katsushika can nest 1

[President Punxsutawney Phil]

with 650 seats, +/-15% deviation and efforts to avoid splitting municipalities and wards:
Tokyo-1: Edogawa (3)
Tokyo-2: Katshushika (2)
Tokyo-3: Adachi (4)
Tokyo-4: Sumida+Koto+the islands (4)
Tokyo-5: Arakawa (1)
Tokyo-6: Taito (1)
Tokyo-7: Chuo+Chiyoda+Minato (2)
Tokyo-8: Bunkyo (1)
Tokyo-9: Kita (1)
Tokyo-10: Toshima+Shinjuku (3)
Tokyo-11: Shinagawa (2)
Tokyo-12: Ota (4)
Tokyo-13: Itabashi (3)
Tokyo-14: Shibuya+Meguro (3)
Tokyo-15: Nerima (4)
Tokyo-16: Nakano+Suginami (4)
Tokyo-17: Setagaya (5)
Tokyo-18: Nish*tokyo (1)
Tokyo-19: Musashino+Koganei+Kokubunji (2)
Tokyo-20: Mitaka (1)
Tokyo-21: Komae+Chofu+Inagi (2)
Tokyo-22: Higashikurume+Kiyose (1)
Tokyo-23: Kodaira (1)
Tokyo-24: Fuchu+Tama (2)
Tokyo-25: Machida (2)
Tokyo-26: Higashimurayama+Higashiyamato+Musashimurayama+Mizuho (2)
Tokyo-27: Kunitachi+Tachikawa+Akishima (2)
Tokyo-28: Hino (1)
Tokyo-29: Hachioji (3)
Tokyo-30: Fussa+Hamura+Akiruno (1)
Tokyo-31: Nish*tama district+Ome (1)
total - 69 members

[President Punxsutawney Phil]

Hokkaido-1: Iburi, Oshima, and Hiyama subprefectures (5)
Hokkaido-2: Shiribeshi subprefecture (1)
Hokkaido-3: Nishi ward in Sapporo (1)
Hokkaido-4: Teine and Kita wards in Sapporo (2)
Hokkaido-5: Atsubetsu, Shiroishi, and Higashi wards in Sapporo (3)
Hokkaido-6: Chuo and Minami wards in Sapporo (2)
Hokkaido-7: Toyohira ward in Sapporo (1)
Hokkaido-8: Kiyota ward in Sapporo+Chitose+Eniwa+Kitahiroshima+Ebetsu (2)
Hokkaido-9: Ishikari city+Ishikari district+Sorachi Subprefecture (2)
Hokkaido-10: Kamikara and Rumoi Subprefectures (3)
Hokkaido-11: Soya and Okhotsk Subprefectures (2)
Hokkaido-12: Hidaka and Tokachi Subprefectures (2)
Hokkaido-13: Nemuro and Koshiro Subprefectures (2)
total - 28 members

[President Punxsutawney Phil]

Aomori-1: Mutsu+Shimokita district+Kamikita district sans Oirase+Misawa (1)
Aomori-2: Hachinohe+Sannohe district+Oirase (1)
Aomori-3: Towada+Hirakawa+Kuroishi+Minamitsugaru district (1)
Aomori-4: Nishimeya+Nish**tsugaru district+Hirosaki (1)
Aomori-5: the rest of Aomori (3)
total - 7 members

[President Punxsutawney Phil]

Akita-1: Akita+Katagami+Minamiakita district+Oga+Kitaakita district (2)
Akita-2: Kitaakita+Ōdate+Kosaka+Kazuno+Noshiro+Yamamoto district  (1)
Akita-3: Nikaho+Yurihonjo+Yuzawa+Ogachi district+Daisen+Misato+Yokote+Semboku (2)
total - 5 members

[President Punxsutawney Phil]

Iwate-1: Ichinoseki+Hiraizumi+Rikuzentakata+Ōfunato+Sumita (1)
Iwate-2: Oshu+Kitakami+Nishiwaga+Kanegasaki+Hanamaki (2)
Iwate-3: Kamaishi+Tōno+Ōtsuchi+Miyaki+Shimohei district (1)
Iwate-4: Morioka+Shiwa district+Shizukuishi (2)
Iwate-5: the rest of Iwate Prefecture (1)
total - 7 members

[President Punxsutawney Phil]

Yamagata-1: Yonezawa+Higashiokitama district+Nishiokitama district+Nagai+Nanyo (1)
Yamagata-2: Kaminoyama+Yamagata city+Tendo+Higashimurayama district (2)
Yamagata-3: Sagae+Nishimurayama district+Tsuruoka+Sakata+Akumi district+Shonai (2)
Yamagata-4: Higashine+Murayama+Obanazawa+Oishida+Shinjo+Mogami district (1)
Total - 6 members

[President Punxsutawney Phil]

Miyagi-1: Igu district+Watari district+Kakuda+Shiroishi+Katta district (1)
Miyagi-2: Natori+Iwanuma+Wakabayashi, Taihoku, and Aoba wards in Sendai (4)
Miyagi-3: Miyagina ward in Sendai (1)
Miyagi-4: Izumi ward in Sendai (1)
Miyagi-5: Tagajō+Shiogama+Miyagi district (1)
Miyagi-6: Tomiya+Kurokawa district+Kami district+Osaki+Kurihara (2)
Miyagi-7: Ishinomaki+Onagawa+Minamisanriku+Tome+Kesennuma+Higashimatsushima+Toda district (2)
total - 12 members

[President Punxsutawney Phil]

Fukushima-1: Fukushima+Date city+Date district (2)
Fukushima-2: Soma district+Soma city+Minamisōma+Futaba district+Tamura (1)
Fukushima-3: Iwaki city (2)
Fukushima-4: Nihommatsu+Motomiya+Adachi district+Kuriyama+Sukagawa+Tamura district (3)
Fukushima-5: Ishikawa district+Higashishirakawa district+Nishishirakawa district less Nishigo+Shirakawa+Iwase district  (1)
Fukushima-6: the rest of Fukushima prefecture (1)
total - 10 members

[President Punxsutawney Phil]

Niigata-1: Niigata city+Tsubame+Yahiko (5)
Niigata-2: Murakami+Tainai+Iwafune district+Shibata+Kitakanbara+Seiro (1)
Niigata-3: Aga+Agano+Gosen+Tagami+Kamo+Sanjo+Mitsuke (2)
Niigata-4: Kashiwazaki+Kariwa+Joetsu+Myoko+Itoigawa+Sado (2)
Niigata-5: the rest of Niigata Prefecture (2)
total - 12 members

[President Punxsutawney Phil]

Tochigi-1: Nasu district+Otawara+Nasukarasuyama+Haga District (1)
Tochigi-2: Nikko+Nasushiobara+Sakura+Yaita+Shioya district+Kanuma (2)
Tochigi-3: Utsonomiya (3)
Tochigi-4: Moka+Shimotsuke+Kaminokawa+Mashiko (1)
Tochigi-5: Oyama+Nogi (1)
Tochigi-6: Tochigi+Sano+Ashikaga (2)
total - 10 members

[President Punxsutawney Phil]

(Image courtesy of Jaichind)
I sought to modulate what this might look like if it pans out.
https://i.ibb.co/QNxxWyB/japan-2040-seats.png
Be warned, the full file is quite large. You can click the spoiler if you want to see the full image, but I decided to link it rather than embed it above.

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