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People → Japan → Shuichi Kuroiwa (黒岩秀一)

People · Japan

Shuichi Kuroiwa (黒岩秀一)

Pyraminx · top 20.4% of 129,321 all-time · competing since July 2005 · 2005KURO02

Shuichi Kuroiwa (黒岩秀一) has been competing for 21 years. His best event is the Pyraminx: a personal-best single of 6.06, set at Osaka Open 2008, puts him in the top 20.4% of the 129,321 people who have ever been ranked in the event, and 222nd in Japan. Across 8 competitions since July 2005, he has put 111 official solves on the record across five events. Solve to solve, his 3×3 times vary about 7% around a typical one, an early reading from 7 counted rounds. His 3×3 best has come down from 19.64 in July 2005 to 17.33, a 12% improvement. Shuichi has entered eight competitions, more competitions than 90% of everyone who has ever competed.

Pyraminx
best event — top 20.4% of 129,321 all-time
6.06
signature single · Osaka Open 2008
111
official solves on the record

Standing, event by event

vs everyone ever ranked
EventPB singlePB averageAll-time standingJapan
Pyraminx6.068.99
top 20.4%222 / 688
3×317.3320.37
top 32.0%1,261 / 3,329
4×41:17.441:26.69
top 53.8%476 / 667
2×28.229.33
top 69.2%785 / 1,021
5×53:04.393:49.27
top 79.5%367 / 420

Percentile against all competitors ever ranked in each event, a fairer measure than raw rank, because the pools differ by a factor of ten.

The line so far

Kyoto Rubik's Cube contest 2005: 19.64Japanese Championship 2005: 19.00Tokyo Open 2006: 20.04Japanese Championship 2006: 17.33Japan Open 2007: 17.94Kashiwa Open 2008: 19.47Japan Open 2008: 22.0917.3322.0910 Jul 20054 Oct 2008

Best single per competition, 3×3. Faster is higher — the axis is the right way up.

The story so far

Competitions

Reading this page: a single is one solve's time · an average is the middle three of five solves, best and worst discarded · a PB is a personal best · a DNF (did not finish) is an attempt with no valid result: a popped piece, an unsolved face, an over-limit memorisation · top X% compares against everyone ever ranked in that event, which is fairer than raw rank because event pools differ tenfold.

The circuit

The people whose scorecards keep turning up next to his.

Next targets

  • A sub-6 Pyraminx single — 25,870 people have one; it is 0.06 away.
  • A sub-15 3×3 single — 69,493 people have one; it is 2.33 away.

Targets move as he improves.