Vigenere Key: 

aaaaaaaaabaaaaaaaaabaaaaaaaaabaaaaaaaaabaaaaaaaaabaaaaaaaaabaaaaaaaaabaaaaaaaaa
baaaaaaaaabaaaaaaaaabaaaaaaaaab


Plaintext: 

abcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcd
efghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghi
jklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmn
oprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprst
uvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxy
zabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcdefghijklmnoprstuvwxyzabcd
efghijklmnoprstuvwxyzxxxxxxxxxxxx


Ciphertext:

abcdefghikklmnoprstvvwxyzabcdffghijklmnpprstuvwxyaabcdefghikklmnoprstvvwxyzabcdf
fghijklmnpprstuvwxyaabcdefghikklmnoprstvvwxyzabcdffghijklmnpprstuvwxyaabcdefghik
klmnoprstvvwxyzabcdffghijklmnpprstuvwxyaabcdefghikklmnoprstvvwxyzabcdffghijklmnp
prstuvwxyaabcdefghikklmnoprstvvwxyzabcdffghijklmnpprstuvwxyaabcdefghikklmnoprstv
vwxyzabcdffghijklmnpprstuvwxyaabcdefghikklmnoprstvvwxyzabcdffghijklmnpprstuvwxya
abcdefghikklmnoprstvvwxyzabcdffghijklmnpprstuvwxyaabcdefghikklmnoprstvvwxyzabcdf
fghijklmnpprstuvwxyaxxxxxxxxxyxx