Block #59,371

1CCLength 8★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/18/2013, 1:43:30 AM · Difficulty 8.9646 · 6,730,686 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
dfce57b76541afd380a2defda2f4333f0263cd99cadd72a3b28dfc53309be001

Height

#59,371

Difficulty

8.964645

Transactions

1

Size

200 B

Version

2

Bits

08f6f2f6

Nonce

181

Timestamp

7/18/2013, 1:43:30 AM

Confirmations

6,730,686

Merkle Root

c83d9b5740dcd7fef329c7044d2956d59a2e55fe90172e287a54051562f761b4
Transactions (1)
1 in → 1 out12.4300 XPM110 B
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.

4.934 × 10⁹⁴(95-digit number)
49345600583979795422…13683882034448806359
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
4.934 × 10⁹⁴(95-digit number)
49345600583979795422…13683882034448806359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.869 × 10⁹⁴(95-digit number)
98691201167959590844…27367764068897612719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.973 × 10⁹⁵(96-digit number)
19738240233591918168…54735528137795225439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.947 × 10⁹⁵(96-digit number)
39476480467183836337…09471056275590450879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.895 × 10⁹⁵(96-digit number)
78952960934367672675…18942112551180901759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.579 × 10⁹⁶(97-digit number)
15790592186873534535…37884225102361803519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.158 × 10⁹⁶(97-digit number)
31581184373747069070…75768450204723607039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.316 × 10⁹⁶(97-digit number)
63162368747494138140…51536900409447214079
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, …
Circulating Supply:57,564,429 XPM·at block #6,790,056 · updates every 60s