[seqfan] Re: Digits of "n" visible in a product
Hans Havermann
gladhobo at teksavvy.com
Mon Jun 1 02:10:15 CEST 2015
> Here are the products for n=1 to 59:
>
> P = 1, 2, 3, 4, 5, 6, 7, 8, 9, 100, 121, 132, 143, 154, 165, 176, 187, 198, 1197, 200, 231, 242, 253, 264, 275, 286, 297, 2184, 2291, 200, 341, 352, 363, 374, 385, 396, 3478, 3382, 3198, 400, 451, 462, 473, 484, 495, 4262, 4277, 4080, 4998, 500, 561, 572, 583, 594, 5555, 5768, 5073, 5684, 5192.
15 165 should be 105
18 198 should be 108
25 275 should be 225
30 200 should be 300
35 385 should be 315
37 3478 should be 3071
45 495 should be 405
46 4262 should be 4462
56 5768 should be 5264
I think term #67 is the first one for which I have no solution < 10^4. Or did you mean for two-digit indices to be visible in products >=10^4 (i.e., with more than two odd digit-positions)?
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