[seqfan] Re: Digits of "n" visible in a product

[Hans Havermann]

> 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)?