Home/Chain Registry/Block #479,953

Block #479,953

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/8/2014, 12:31:11 AM · Difficulty 10.5111 · 6,346,639 confirmations

2CC

Cunningham Chain of the Second Kind

A sequence where each prime is double the previous prime minus one.

Block Header

Block Hash

2e4ca281c1e0b223b5c03421f836ea3ee7fb75e9c2fb9b4c97df8c540e501dae

View on Chainz ↗

Height

#479,953

Difficulty

10.511119

Transactions

Size

905 B

Version

Bits

0a82d8aa

Nonce

93,771

Timestamp

4/8/2014, 12:31:11 AM

Confirmations

6,346,639

Merkle Root

5a595753b5c23e1fbf1bc33dd5900e5fe397757fc5de12eb1a0d60cdbd4d1376

Transactions (1)

Coinbase5a595753b5c23e…0d60cdbd4d1376

1 in → 22 out9.0400 XPM811 B

ANNg88pG…ppn21sTe AQ8QAT3J…rCFKuVbR ATKK7iFz…wZm46KN1 AWMrD5hP…ZwsoxvZ3 ALqxX1WA…hsKjbnXn

Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

1.272 × 10¹⁰⁵(106-digit number)

12723233478077645536…60089785177820450560

Discovered Prime Numbers

p_k = 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

origin + 1

1.272 × 10¹⁰⁵(106-digit number)

12723233478077645536…60089785177820450561

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^1 × origin + 1

2.544 × 10¹⁰⁵(106-digit number)

25446466956155291073…20179570355640901121

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^2 × origin + 1

5.089 × 10¹⁰⁵(106-digit number)

50892933912310582147…40359140711281802241

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^3 × origin + 1

1.017 × 10¹⁰⁶(107-digit number)

10178586782462116429…80718281422563604481

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^4 × origin + 1

2.035 × 10¹⁰⁶(107-digit number)

20357173564924232858…61436562845127208961

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^5 × origin + 1

4.071 × 10¹⁰⁶(107-digit number)

40714347129848465717…22873125690254417921

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^6 × origin + 1

8.142 × 10¹⁰⁶(107-digit number)

81428694259696931435…45746251380508835841

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^7 × origin + 1

1.628 × 10¹⁰⁷(108-digit number)

16285738851939386287…91492502761017671681

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^8 × origin + 1

3.257 × 10¹⁰⁷(108-digit number)

32571477703878772574…82985005522035343361

Verify on FactorDB ↗Wolfram Alpha ↗

×2−1 →

2^9 × origin + 1

6.514 × 10¹⁰⁷(108-digit number)

65142955407757545148…65970011044070686721

Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Cunningham Chain of the Second Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

View full Prime Chain Discovery page →

★★☆☆☆

Rarity

UncommonChain length 10

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)

Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …

Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height

getblockhash 479953

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data

getblock 2e4ca281c1e0b223b5c03421f836ea3ee7fb75e9c2fb9b4c97df8c540e501dae

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #479,953 on Chainz ↗

Block #479,953

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