The term three-centered arch is identified in base64 scheme by the sequence dGhyZWUtY2VudGVyZWQgYXJjaA==, while the MD5 signature is equal to a97908160c642825658e23acf2836b86. The ASCII encoding of three-centered arch in hexadecimal notation is 74687265652d63656e74657265642061726368.