# [seqfan] Re: Two related simple infinite sequences

Amiram Eldar amiram.eldar at gmail.com
Thu Jan 19 18:54:21 CET 2023

```Since no one tried to answer, here is my guess, which works for all the
given terms:
s1 is the sequence A339910 (without the first term) interleaved with
A339910 - 1, and s2 is the sequence A322840 interleaved with A322840 + 1.

On Mon, Jan 16, 2023 at 4:03 PM zak seidov via SeqFan <seqfan at list.seqfan.eu>
wrote:

> s1 = {5, 4, 7, 6, 9, 8, 11, 10, 13, 12, 17, 16, 19, 18, 21, 20, 23, 22,
> 25, 24, 29, 28, 31, 30, 33, 32, 37, 36, 41, 40, 43, 42, 46, 45, 47, 46, 49,
> 48, 51, 50, 53, 52, 55, 54, 57, 56, 59, 58, 61, 60, 65, 64, 67, 66, 69, 68,
> 71, 70, 73, 72, 77, 76, 79, 78, 81, 80, 82, 81, 83, 82, 85, 84, 89, 88, 91,
> 90, 93, 92, 97, 96, 101, 100, 103, 102, 105, 104, 106, 105, 107, 106, 109,
> 108, 111, 110, 113, 112, 115, 114, 118, 117, 121, 120, 127, 126, 129, 128,
> 131, 130, 133, 132, 137, 136, 139, 138, 141, 140, 145, 144, 149, 148, 151,
> 150, 153, 152, 155, 154, 157, 156, 161, 160, 163, 162, 166, 165, 167, 166,
> 169, 168, 173, 172, ...}
>
> s2 = {2, 1, 4, 3, 6, 5, 8, 7, 12, 11, 14, 13, 16, 15, 18, 17, 20, 19, 24,
> 23, 27, 26, 30, 29, 32, 31, 36, 35, 38, 37, 40, 39, 42, 41, 44, 43, 48, 47,
> 50, 49, 52, 51, 54, 53, 56, 55, 60, 59, 62, 61, 63, 62, 64, 63, 66, 65, 68,
> 67, 70, 69, 72, 71, 74, 73, 75, 74, 78, 77, 80, 79, 84, 83, 88, 87, 90, 89,
> 92, 91, 96, 95, 98, 97, 100, 99, 102, 101, 104, 103, 108, 107, 110, 109,
> 112, 111, 114, 113, 116, 115, 120, 119, 124, 123, 126, 125, 128, 127, 130,
> 129, 132, 131, 135, 134, 138, 137, 140, 139, 144, 143, 147, 146, 150, 149,
> 152, 151, 156, 155, 158, 157, 160, 159, 162, 161, 164, 163, 168, 167, 170,
> 169, 174, 173, 176, 175, ...}
>
> Can anyone guess what s1 and s2 are?
> Zak Seidov
> zakseidov at Yahoo.com
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>
```