Block #327,301

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/24/2013, 11:25:03 AM · Difficulty 10.1740 · 6,467,546 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5d723280b40220861097a5e4c4e5e7b16df0ef1fdea5fcb066422ea1ccaa674a

Height

#327,301

Difficulty

10.173996

Transactions

6

Size

22.26 KB

Version

2

Bits

0a2c8b03

Nonce

12,156

Timestamp

12/24/2013, 11:25:03 AM

Confirmations

6,467,546

Merkle Root

7456f36dcc7c94b231f272edfb991b62a003b3307c58ad764b07838a122d9b72
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.

2.340 × 10⁹⁴(95-digit number)
23405233852471919026…59224838152884246049
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.

1
origin − 1
2.340 × 10⁹⁴(95-digit number)
23405233852471919026…59224838152884246049
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.681 × 10⁹⁴(95-digit number)
46810467704943838052…18449676305768492099
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.362 × 10⁹⁴(95-digit number)
93620935409887676104…36899352611536984199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.872 × 10⁹⁵(96-digit number)
18724187081977535220…73798705223073968399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.744 × 10⁹⁵(96-digit number)
37448374163955070441…47597410446147936799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.489 × 10⁹⁵(96-digit number)
74896748327910140883…95194820892295873599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.497 × 10⁹⁶(97-digit number)
14979349665582028176…90389641784591747199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.995 × 10⁹⁶(97-digit number)
29958699331164056353…80779283569183494399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.991 × 10⁹⁶(97-digit number)
59917398662328112706…61558567138366988799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.198 × 10⁹⁷(98-digit number)
11983479732465622541…23117134276733977599
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 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
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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, …
Circulating Supply:57,602,806 XPM·at block #6,794,846 · updates every 60s
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