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Old 2019-01-22, 17:02   #89
henryzz
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357 = 8-2+5*8*9+L3D[-9]
359 = -8/2+5*8*9 + L3D[3]
360 = 8-2+5*8*9+L3D[-6]
361 = 8+2+5*8*9+L3D[-9]
362 to 370 = 8-2+5*8*9 + L3D[-4 to 4]
371 to 374 = 8+2+5*8*9 + L3D[1 to 4]
375 to 380 = 8*2+5*8*9 + L3D[-1 to 4]
381 = (8+2)*5*8 + L4D[-19]
382 to 390 = 8+(2+5*8)*9 + L3D[-4 to 4]
391 to 413 = (8+2)*5*8 + L4D[-9 to 13]
414 to 418 = (8-2+5*8)*9 + L3D[0 to 4]
419 = (8+2)*5*8 + L4D[19]
420 = (8-2+5*8)*9 + L3D[6]
421 = (8+2)*5*8 + L4D[21]
422 to 424 = (8-2+5*8)*9 + L3D[8 to 10]

And that's enough from me for a bit.
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Old 2019-01-23, 16:35   #90
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Quote:
Originally Posted by henryzz View Post
How didn't I spot that trivial 5*8*9=360?
My math skills are so trivial that I find this non-trivial:

Someone born in 33 was 45 in 78.

You have to be old enough to get it. At least I qualify there!
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Old 2019-01-29, 15:36   #91
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425 is still needed.

426 = ((8+2)+5*8)*9 - 9*3+3
427 = 8*(2+5)*8 + L4D[-21]
428 = (-8+(2+5)*8)*9 +L3D[-4]
429 to 431 = 8*(2+5)*8 + L4D[-19 to -17]
432 = 8/2*(5+8)*9 - (9+3)*3
433 = 8*(2+5)*8 + L4D[-15]
434 to 461 = 8*(2+5)*8 + L4D[-13 to 13]
462 = 8/2*(5+8)*9 + L3D[-6]
463 = (8+2)*(5*8+(9+9)/3)+3
464 to 472 = 8/2*(5+8)*9 + L3D[-4 to 4]

Last fiddled with by henryzz on 2019-01-29 at 15:36
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Old 2019-01-29, 16:16   #92
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Quote:
Originally Posted by henryzz View Post
425 is still needed.
It's a multiple of 5 so: 8+2+5*(8+9*9-3-3)
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Old 2019-01-30, 08:22   #93
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473 isn't much different from 425.

473 8+2+5*(8+9*9+3)+3
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Old 2019-01-30, 09:41   #94
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We can get 504 as a base from the first 5 digits

504 = (8*2+5*8)*9

So that gives us 474 with

474 = (8*2+5*8)*9-(9*3+3)
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Old 2019-01-30, 11:07   #95
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a bunch of L3D solutions:
15 = 9+3+3
18 = 9+3*3
24 = 9*3-3
30 = 9*3+3
36 = (9+3)*3

Various numbers can be solved based on:
490 = (8+2)*(5*8+9)

475 = (8+2)*(5*8+9) + L3D[-15]
480 to 482 = (8+2)*(5*8+9) + L3D[-10 to -8]
484 = (8+2)*(5*8+9) + L3D[-6]
486 to 494 = (8+2)*(5*8+9) + L3D[-4 to 4]
496 = (8+2)*(5*8+9) + L3D[6]
498 to 500 = (8+2)*(5*8+9) + L3D[8 to 10]
505 = (8+2)*(5*8+9) + L3D[15]
508 = (8+2)*(5*8+9) + L3D[18]
514 = (8+2)*(5*8+9) + L3D[24]
520 = (8+2)*(5*8+9) + L3D[30]
526 = (8+2)*(5*8+9) + L3D[36]

retina's 504 produces:

495 = (8*2+5*8)*9 + L3D[-9]
501 to 504 = (8*2+5*8)*9 + L3D[-3 to 0]
506 to 507 = (8*2+5*8)*9 + L3D[2 to 3]
510 = (8*2+5*8)*9 + L3D[6]
512 to 513 = (8*2+5*8)*9 + L3D[8 to 9]
519 = (8*2+5*8)*9 + L3D[15]
522 = (8*2+5*8)*9 + L3D[18]
528 = (8*2+5*8)*9 + L3D[24]
534 = (8*2+5*8)*9 + L3D[30]
540 = (8*2+5*8)*9 + L3D[36]
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Old 2019-01-31, 14:57   #96
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496 = 8*2*(5*8-9) produces:
478 = 8*2*(5*8-9) + L3D[-18]
497 = 8*2*(5*8-9) + L3D[1]
511 = 8*2*(5*8-9) + L3D[15]
532 = 8*2*(5*8-9) + L3D[36]

510 = (8-2)*5*(8+9) produces:
509 = (8-2)*5*(8+9) + L3D[-1]
516 = (8-2)*5*(8+9) + L3D[6]
518 = (8-2)*5*(8+9) + L3D[8]
525 = (8-2)*5*(8+9) + L3D[15]
546 = (8-2)*5*(8+9) + L3D[36]

512 = 8+(2+5)*8*9 produces:
476 = 8+(2+5)*8*9 + L3D[-36]
515 = 8+(2+5)*8*9 + L3D[3]
521 = 8+(2+5)*8*9 + L3D[9]
527 = 8+(2+5)*8*9 + L3D[15]
530 = 8+(2+5)*8*9 + L3D[18]
536 = 8+(2+5)*8*9 + L3D[24]
542 = 8+(2+5)*8*9 + L3D[30]
548 = 8+(2+5)*8*9 + L3D[36]

This leaves only 4 left to reach 500: 477, 479, 483, 485
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Old 2019-01-31, 15:13   #97
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Another 5 digit base

468 = 8/(2/(5+8)/9)
Another way to write it is 8/(2/(5+8))*9

Leads to

477 = 8/(2/(5+8)/9)+9-3+3

Last fiddled with by retina on 2019-01-31 at 15:16
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Old 2019-01-31, 16:07   #98
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That 468 also leads to:
483 = 8/(2/(5+8)/9) + L3D[15]
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Old 2019-01-31, 16:16   #99
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479 = (8+2)*5+8*9*(9-3)-3

I'll leave it to someone else to discover 485
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