Block #60,268

1CCLength 8★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/18/2013, 7:01:49 AM · Difficulty 8.9685 · 6,729,482 confirmations

1CC

Cunningham Chain of the First Kind

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

Block Header

Block Hash

6314101c468b1ccc924963f57d02277147eda453fc622d770a7518d9a8195d88

View on Chainz ↗

Height

#60,268

Difficulty

8.968508

Transactions

Size

1.24 KB

Version

Bits

08f7f026

Nonce

251

Timestamp

7/18/2013, 7:01:49 AM

Confirmations

6,729,482

Merkle Root

8b6b8b81a2d977c935714d3ced3adea91c41fefdb990c82e52ecf33edbe45d7f

Transactions (3)

Coinbasee5199d8394fe03…dc24ea89ac852e

1 in → 1 out12.4400 XPM110 B

AeSzM5KP…GwMqxeHB

81c2ffdac3f96d…eef2542df83c98

7 in → 1 out528.7050 XPM913 B

AUgWGKxh…domfgFq7

70e8b4196e428b…25fdff86c9e8da

1 in → 1 out13.6900 XPM158 B

ASZuraus…HrQkTUKT

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.

3.598 × 10⁹⁹(100-digit number)

35987144579737470836…82134527622166845809

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

3.598 × 10⁹⁹(100-digit number)

35987144579737470836…82134527622166845809

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^1 × origin − 1

7.197 × 10⁹⁹(100-digit number)

71974289159474941672…64269055244333691619

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^2 × origin − 1

1.439 × 10¹⁰⁰(101-digit number)

14394857831894988334…28538110488667383239

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^3 × origin − 1

2.878 × 10¹⁰⁰(101-digit number)

28789715663789976669…57076220977334766479

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^4 × origin − 1

5.757 × 10¹⁰⁰(101-digit number)

57579431327579953338…14152441954669532959

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^5 × origin − 1

1.151 × 10¹⁰¹(102-digit number)

11515886265515990667…28304883909339065919

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^6 × origin − 1

2.303 × 10¹⁰¹(102-digit number)

23031772531031981335…56609767818678131839

Verify on FactorDB ↗Wolfram Alpha ↗

×2+1 →

2^7 × origin − 1

4.606 × 10¹⁰¹(102-digit number)

46063545062063962670…13219535637356263679

Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 8 consecutive prime numbers forming a Cunningham Chain of the First 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.

★☆☆☆☆

Rarity

CommonChain length 8

Found in most blocks. The baseline for Primecoin's proof-of-work.

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 1CC formula:

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

Cross-reference on Chainz Explorer