diff --git a/packages/cactus-plugin-htlc-eth-besu/package.json b/packages/cactus-plugin-htlc-eth-besu/package.json
index f6395e1dd6d..17ce2e990ef 100644
--- a/packages/cactus-plugin-htlc-eth-besu/package.json
+++ b/packages/cactus-plugin-htlc-eth-besu/package.json
@@ -73,7 +73,7 @@
     "@hyperledger/cactus-plugin-ledger-connector-besu": "1.2.0",
     "@hyperledger/cactus-test-tooling": "1.2.0",
     "axios": "0.21.4",
-    "bn.js": "5.1.1",
+    "bn.js": "5.2.1",
     "dotenv": "16.0.3",
     "ethers": "6.3.0",
     "express": "4.17.1",
diff --git a/packages/cactus-plugin-htlc-eth-besu/src/main/typescript/private-htlc-helper.ts b/packages/cactus-plugin-htlc-eth-besu/src/main/typescript/private-htlc-helper.ts
index 08b3428f602..5cedf6f7620 100644
--- a/packages/cactus-plugin-htlc-eth-besu/src/main/typescript/private-htlc-helper.ts
+++ b/packages/cactus-plugin-htlc-eth-besu/src/main/typescript/private-htlc-helper.ts
@@ -39,7 +39,7 @@ const main = async () => {
     const GENERATOR = new BN(11);
     const MODULUS = new BN(109);
     const SECRET_ALICE = new BN(3);
-    const SECRET_BOB = new BN(5);
+    const BOB_INPUT_TO_Z = new BN(50);
 
     const exponentiationAliceHashLock = modExp(
       GENERATOR,
@@ -47,18 +47,22 @@ const main = async () => {
       SECRET_ALICE,
     );
     const HASH_SECRET_ALICE = toBytes32(exponentiationAliceHashLock);
-    console.log(`Hashed secret from Alice: ${HASH_SECRET_ALICE}`);
-    console.log(`Secret from Alice: ${toBytes32(SECRET_ALICE)}`);
+    console.log(`Ya: ${HASH_SECRET_ALICE}`);
+    console.log(`sa: ${toBytes32(SECRET_ALICE)}`);
 
-    const Z = modExp(GENERATOR, MODULUS, SECRET_ALICE.add(SECRET_BOB));
+    const Z = modExp(GENERATOR, MODULUS, SECRET_ALICE.mul(BOB_INPUT_TO_Z));
     const BYTES_32_Z = toBytes32(Z);
-    console.log(`BYTES 32 Z: ${BYTES_32_Z}`);
+    console.log(`Z: ${BYTES_32_Z}`);
 
-    // equivalent to g^(sa + z)
-    const HASH_SECRET_BOB = toBytes32(
-      modExp(GENERATOR, MODULUS, Z.add(SECRET_ALICE)),
-    );
-    console.log(`Hashed secret from Bob: ${HASH_SECRET_BOB}`);
+    const YB = exponentiationAliceHashLock
+      .mul(modExp(GENERATOR, MODULUS, new BN(Z.toNumber())))
+      .mod(MODULUS);
+    console.log(`Yb: ${YB}`);
+    console.log(`Yb: ${toBytes32(YB)}`);
+
+    const sb = SECRET_ALICE.add(Z);
+    console.log(`sb: ${sb}`);
+    console.log(`sb: ${toBytes32(sb)}`);
   } catch (error) {
     console.log("There has been an error ", error);
     throw new Error();