the shortest ecdsa secp256k1 outputs I’ve ever seen have

```
x value = 3b78ce563f89a0ed9414f5aa28ad0d96d6795f9c63
0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a0 --> 0x3b78ce563f89a0ed9414f5aa28ad0d96d6795f9c63, 0x3f3979bf72ae8202983dc989aec7f2ff2ed91bdd69ce02fc0700ca100e59ddf3
0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a1 --> 0x3b78ce563f89a0ed9414f5aa28ad0d96d6795f9c63, 0xc0c686408d517dfd67c2367651380d00d126e4229631fd03f8ff35eef1a61e3c
```

in your ecdsa function, if you use

```
p = 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141
```

then you can derive the above results using

```
((p-1)/2) = 0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a0
```

or

```
((p+1)/2) = 0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a1
```

if there is anything smaller, i’d be curious to see it.

**Edit**

due to comments, I have been directed to a testnet tx that suggests maybe you can get R=1. thanks to amaclin.

testnet tx c6c232a36395fa338da458b86ff1327395a9afc28c5d2daa4273e410089fd433

this tx appears to validate,

there are also others,

c42bea01f1387072772759f32ad860a680e0eea5664732bf2057a66780e7a25d

23202c2534be0567d4b339142f8a9a53545123eb61f61717fdedbef8effc53e0

maybe even more, please add to comments if so.

if I validate the public key signature

```
026d2204a9535443657a88a0724fbd49a0e78d305f50a82f2cc9dd9bea10a6c5cd
```

taken from the testnet tx

```
c6c232a36395fa338da458b86ff1327395a9afc28c5d2daa4273e410089fd433
```

it gives this point where the x = 1

```
(0x01, 0xbde70df51939b94c9c24979fa7dd04ebd9b3572da7802290438af2a681895441)
```

while I can’t verify that this point is actually on the sep256k1 curve, it seems to behave like it is, so this is a very interesting one.

if I multiply this point several times by 0x5363ad4cc05c30e0a5261c028812645a122e22ea20816678df02967c1b23bd72 (lambda value from here)

it produces this cycle of points (3 points with same Y)

```
(0x7ae96a2b657c07106e64479eac3434e99cf0497512f58995c1396c28719501ee, 0xbde70df51939b94c9c24979fa7dd04ebd9b3572da7802290438af2a681895441)
(0x851695d49a83f8ef919bb86153cbcb16630fb68aed0a766a3ec693d68e6afa40, 0xbde70df51939b94c9c24979fa7dd04ebd9b3572da7802290438af2a681895441)
(0x01, 0xbde70df51939b94c9c24979fa7dd04ebd9b3572da7802290438af2a681895441)
```

if I do the same with the inverse of the point, I get these (inverses of above)

```
(0x7ae96a2b657c07106e64479eac3434e99cf0497512f58995c1396c28719501ee, 0x4218f20ae6c646b363db68605822fb14264ca8d2587fdd6fbc750d587e76a7ee)
(0x851695d49a83f8ef919bb86153cbcb16630fb68aed0a766a3ec693d68e6afa40, 0x4218f20ae6c646b363db68605822fb14264ca8d2587fdd6fbc750d587e76a7ee)
(0x1, 0x4218f20ae6c646b363db68605822fb14264ca8d2587fdd6fbc750d587e76a7ee)
```

The X value

```
0x7ae96a2b657c07106e64479eac3434e99cf0497512f58995c1396c28719501ee
```

in some of those results, also happens to be the beta value from here