[seqfan] Re: 2019 must be read here as 201^9

M. F. Hasler oeis at hasler.fr
Thu Nov 21 15:51:10 CET 2019


On Thu, Nov 21, 2019 at 7:48 AM Éric Angelini <eric.angelini at skynet.be>
wrote:

> We have a hit if a^b shows b
> (with a = any integer and b = any digit).
> (2019 must be read hereunder as 201^9)
>
> The seq S begins (I guess):
> S=11,26,37,46,52,55,56,57,59,66,67,69,
> 73,74,76,78,84,86,87,95,97,99,101,111,
> 115,119,121,128,129,131,136,137,138,139,
> 141,144,145,146,148,...
>

I get some others, starting with 39:
select( t->setsearch(Set(digits((t\10)^(t%10))),t%10),[0..9999])
= [11, 26, 37, 39, 46, 52, 55, 56, 57, 59, 66, 67, 69, 73, 74, 76, 78, 84,
86, 87, 95, 97, 99,
101, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 128, 129, 131, 136,
137, 138, 139, 141, 144, 145, 146, 148, 151, 152, 153, 155, 156, 157, 158,
159, 161, 162, 165, 166, 169, 171, 172, 173, 175, 176, 177, 179, 181, 182,
183, 184, 185, 189, 191, 197, 198, 199,
206, 211, 214, 216, 218, 219, 224, 225, 227, 228, 229, 232, 234, 237, 238,
243, 246, 247, 252, 255, 256, 258, 259, 264, 266, 267, 268, 269, 272, 273,
274, 278, 279, 284, 288, 289, 293, 295, 297, 299, ...]

It's easy to see that all numbers ending in 11, 37, 46, 52, 55, 59, 66, 69,
73, 84, 97, 99 are in the sequence

- Maximilian

Example:
> 144-->14^4=38416 (hit "4")
> 145-->14^5=537824 (hit "5")
> 146-->14^6=7529536 (hit "6")
> 147-->14^7=105413504 (no "7" = no hit)
> 148-->14^8=1475789056 (hit 8")
> etc.
> Best,
> É.
> (my first 11 terms are not in the OEIS
> and don't deserve it, perhaps!-)
> Best,
> É.
>
>
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>


-- 
Maximilian



More information about the SeqFan mailing list