Recently, I was quite surprised, when I saw that there are six different n-values, matching different b-values in secp256k1:
+-----+---------------------------------------------------------------------+
| b | n |
+-----+---------------------------------------------------------------------+
| 0x1 | 0xfffffffffffffffffffffffffffffffe06f23032560e83e138ea6fc857fb4794 |
| 0x2 | 0x1000000000000000000000000000000014551231950b75fc4402da1712fc9b71f |
| 0x3 | 0xffffffffffffffffffffffffffffffff4c43534ba6c5e3a57918113a87c50283 |
| 0x4 | 0x100000000000000000000000000000000b3bcacb4593a1c5a86e7eec3783af5dd |
| 0x6 | 0x100000000000000000000000000000001f90dcfcda9f17c1ec7159035a804b0cc |
| 0x7 | 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141 |
+-----+---------------------------------------------------------------------+
They are repeating over and over again, as b-value is incremented. However, it also seems they can be connected in pairs, each giving the same sum:
+-----+---------------------------------------------------------------------+
| b | n |
+-----+---------------------------------------------------------------------+
| 0x1 | 0xfffffffffffffffffffffffffffffffe06f23032560e83e138ea6fc857fb4794 |
| 0x6 | 0x100000000000000000000000000000001f90dcfcda9f17c1ec7159035a804b0cc |
| sum | 0x1fffffffffffffffffffffffffffffffffffffffffffffffffffffffdfffff860 |
+-----+---------------------------------------------------------------------+
| 0x2 | 0x1000000000000000000000000000000014551231950b75fc4402da1712fc9b71f |
| 0x7 | 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141 |
| sum | 0x1fffffffffffffffffffffffffffffffffffffffffffffffffffffffdfffff860 |
+-----+---------------------------------------------------------------------+
| 0x3 | 0xffffffffffffffffffffffffffffffff4c43534ba6c5e3a57918113a87c50283 |
| 0x4 | 0x100000000000000000000000000000000b3bcacb4593a1c5a86e7eec3783af5dd |
| sum | 0x1fffffffffffffffffffffffffffffffffffffffffffffffffffffffdfffff860 |
+-----+---------------------------------------------------------------------+
The question is: does it mean that there is some kind of connection between y^2=x^3+7, and for example y^2=x^3+2? Or maybe there is another connection, where points on curves with identical p-value and n-value can be mapped? Does it mean, that if we have b=0x7, where there are "n" points, and for example b=0xc curve also has the same amount of points, then does it mean we can map them 1:1?