block23.

> encode_abi(
  ["uint256[]", "uint256[]", "uint256[]"],
  [[0xa1, 0xa2, 0xa3], [0xb1, 0xb2, 0xb3], [0xc1, 0xc2, 0xc3]]
).hex()

/************* HEAD (32*3 bytes) *************/
// arg1: look at position 0x60 for array data
0000000000000000000000000000000000000000000000000000000000000060
// arg2: look at position 0xe0 for array data
00000000000000000000000000000000000000000000000000000000000000e0
// arg3: look at position 0x160 for array data
0000000000000000000000000000000000000000000000000000000000000160

/************* TAIL (128**3 bytes) *************/
// position 0x60. Data for arg1.
// Length followed by elements.
0000000000000000000000000000000000000000000000000000000000000003
00000000000000000000000000000000000000000000000000000000000000a1
00000000000000000000000000000000000000000000000000000000000000a2
00000000000000000000000000000000000000000000000000000000000000a3

// position 0xe0. Data for arg2.
0000000000000000000000000000000000000000000000000000000000000003
00000000000000000000000000000000000000000000000000000000000000b1
00000000000000000000000000000000000000000000000000000000000000b2
00000000000000000000000000000000000000000000000000000000000000b3

// position 0x160. Data for arg3.
0000000000000000000000000000000000000000000000000000000000000003
00000000000000000000000000000000000000000000000000000000000000c1
00000000000000000000000000000000000000000000000000000000000000c2
00000000000000000000000000000000000000000000000000000000000000c3