Comprender la representación de Bytes16 en Solidity

Tengo una función simple que imprime byte a byte el valor de bytes16 0x20010db80000000000000000000000001 y obtengo el siguiente resultado.

['0x20', '0x01', '0x0d', '0xb7', '0xff', '0xff', '0xff', '0x65' ]

[ '0x20', '0x7e', '0x22', '0x36', '0x66', '0xc0', '0x00', '0x00' ]

no debe ser??

['0x20', '0x01', '0x0d', '0xb8', '0x00', '0x00', '0x00', '0x00' ]

[ '0x00', '0x00', '0x00', '0x00', '0x00', '0x00', '0x00', '0x01' ]

¿Por qué no?

Aquí el código:

function print1(bytes16 a) public 
returns (bytes1,bytes1,bytes1,bytes1,bytes1,bytes1,bytes1,bytes1){
return (a[0],a[1],a[2],a[3],a[4],a[5],a[6],a[7]);}


function print2(bytes16 a) public returns
(bytes1,bytes1,bytes1,bytes1,bytes1,bytes1,bytes1,bytes1){
return (a[8],a[9],a[10],a[11],a[12],a[13],a[14],a[15]);}    

Paso a reproducir:

print1(0x20010db8000000000000000000000001);
print2(0x20010db8000000000000000000000001);