M51 arithmetic - Page 9

henryzz · 2019-01-22, 17:02

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.

PhilF · 2019-01-23, 16:35

Quote:

Originally Posted by henryzz

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!

henryzz · 2019-01-29, 15:36

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]

retina · 2019-01-29, 16:16

Quote:

Originally Posted by henryzz

425 is still needed.

It's a multiple of 5 so: 8+2+5*(8+9*9-3-3)

retina · 2019-01-30, 08:22

473 isn't much different from 425.

473 8+2+5*(8+9*9+3)+3

retina · 2019-01-30, 09:41

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)

henryzz · 2019-01-30, 11:07

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]

henryzz · 2019-01-31, 14:57

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

retina · 2019-01-31, 15:13

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

henryzz · 2019-01-31, 16:07

That 468 also leads to:
483 = 8/(2/(5+8)/9) + L3D[15]

retina · 2019-01-31, 16:16

479 = (8+2)*5+8*9*(9-3)-3

I'll leave it to someone else to discover 485

2019-01-29, 15:36	#91
henryzz Just call me Henry "David" Sep 2007 Cambridge (GMT/BST) 2³×3×5×7² Posts	425 is still needed. 426 = ((8+2)+58)9 - 93+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)(58+(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

2019-01-31, 15:13	#97
retina Undefined "The unspeakable one" Jun 2006 My evil lair 2²·1,549 Posts	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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2019-01-22, 17:02	#89
henryzz Just call me Henry "David" Sep 2007 Cambridge (GMT/BST) 5880₁₀ Posts	357 = 8-2+589+L3D[-9] 359 = -8/2+589 + L3D[3] 360 = 8-2+589+L3D[-6] 361 = 8+2+589+L3D[-9] 362 to 370 = 8-2+589 + L3D[-4 to 4] 371 to 374 = 8+2+589 + L3D[1 to 4] 375 to 380 = 82+589 + L3D[-1 to 4] 381 = (8+2)58 + L4D[-19] 382 to 390 = 8+(2+58)9 + L3D[-4 to 4] 391 to 413 = (8+2)58 + L4D[-9 to 13] 414 to 418 = (8-2+58)9 + L3D[0 to 4] 419 = (8+2)58 + L4D[19] 420 = (8-2+58)9 + L3D[6] 421 = (8+2)58 + L4D[21] 422 to 424 = (8-2+58)*9 + L3D[8 to 10] And that's enough from me for a bit.

2019-01-30, 08:22	#93
retina Undefined "The unspeakable one" Jun 2006 My evil lair 2²×1,549 Posts	473 isn't much different from 425. 473 8+2+5(8+99+3)+3

2019-01-30, 09:41	#94
retina Undefined "The unspeakable one" Jun 2006 My evil lair 2²×1,549 Posts	We can get 504 as a base from the first 5 digits 504 = (82+58)9 So that gives us 474 with 474 = (82+58)9-(9*3+3)

2019-01-30, 11:07	#95
henryzz Just call me Henry "David" Sep 2007 Cambridge (GMT/BST) 2³·3·5·7² Posts	a bunch of L3D solutions: 15 = 9+3+3 18 = 9+33 24 = 93-3 30 = 93+3 36 = (9+3)3 Various numbers can be solved based on: 490 = (8+2)(58+9) 475 = (8+2)(58+9) + L3D[-15] 480 to 482 = (8+2)(58+9) + L3D[-10 to -8] 484 = (8+2)(58+9) + L3D[-6] 486 to 494 = (8+2)(58+9) + L3D[-4 to 4] 496 = (8+2)(58+9) + L3D[6] 498 to 500 = (8+2)(58+9) + L3D[8 to 10] 505 = (8+2)(58+9) + L3D[15] 508 = (8+2)(58+9) + L3D[18] 514 = (8+2)(58+9) + L3D[24] 520 = (8+2)(58+9) + L3D[30] 526 = (8+2)(58+9) + L3D[36] retina's 504 produces: 495 = (82+58)9 + L3D[-9] 501 to 504 = (82+58)9 + L3D[-3 to 0] 506 to 507 = (82+58)9 + L3D[2 to 3] 510 = (82+58)9 + L3D[6] 512 to 513 = (82+58)9 + L3D[8 to 9] 519 = (82+58)9 + L3D[15] 522 = (82+58)9 + L3D[18] 528 = (82+58)9 + L3D[24] 534 = (82+58)9 + L3D[30] 540 = (82+58)9 + L3D[36]

2019-01-31, 14:57	#96
henryzz Just call me Henry "David" Sep 2007 Cambridge (GMT/BST) 2³·3·5·7² Posts	496 = 82(58-9) produces: 478 = 82(58-9) + L3D[-18] 497 = 82(58-9) + L3D[1] 511 = 82(58-9) + L3D[15] 532 = 82(58-9) + 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)89 produces: 476 = 8+(2+5)89 + L3D[-36] 515 = 8+(2+5)89 + L3D[3] 521 = 8+(2+5)89 + L3D[9] 527 = 8+(2+5)89 + L3D[15] 530 = 8+(2+5)89 + L3D[18] 536 = 8+(2+5)89 + L3D[24] 542 = 8+(2+5)89 + L3D[30] 548 = 8+(2+5)8*9 + L3D[36] This leaves only 4 left to reach 500: 477, 479, 483, 485

2019-01-31, 16:07	#98
henryzz Just call me Henry "David" Sep 2007 Cambridge (GMT/BST) 16F8₁₆ Posts	That 468 also leads to: 483 = 8/(2/(5+8)/9) + L3D[15]

2019-01-31, 16:16	#99
retina Undefined "The unspeakable one" Jun 2006 My evil lair 2²×1,549 Posts	479 = (8+2)5+89*(9-3)-3 I'll leave it to someone else to discover 485