Block #337,019

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/31/2013, 9:20:03 AM · Difficulty 10.1384 · 6,455,631 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e59ac4c27794168a1b2a4be78b788d32ff26b8dcd1f6bd8e867214183f88c15b

Height

#337,019

Difficulty

10.138369

Transactions

10

Size

4.90 KB

Version

2

Bits

0a236c2d

Nonce

20,149

Timestamp

12/31/2013, 9:20:03 AM

Confirmations

6,455,631

Merkle Root

2cb90c0247ffbbe0d3ff674a1be0386a529039297fbb6e4f54a5d1d8271d1018
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.

2.019 × 10⁹⁹(100-digit number)
20194629511157436951…83904449737176567679
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
2.019 × 10⁹⁹(100-digit number)
20194629511157436951…83904449737176567679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.038 × 10⁹⁹(100-digit number)
40389259022314873902…67808899474353135359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.077 × 10⁹⁹(100-digit number)
80778518044629747804…35617798948706270719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.615 × 10¹⁰⁰(101-digit number)
16155703608925949560…71235597897412541439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.231 × 10¹⁰⁰(101-digit number)
32311407217851899121…42471195794825082879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.462 × 10¹⁰⁰(101-digit number)
64622814435703798243…84942391589650165759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.292 × 10¹⁰¹(102-digit number)
12924562887140759648…69884783179300331519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.584 × 10¹⁰¹(102-digit number)
25849125774281519297…39769566358600663039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.169 × 10¹⁰¹(102-digit number)
51698251548563038594…79539132717201326079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.033 × 10¹⁰²(103-digit number)
10339650309712607718…59078265434402652159
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:57,585,168 XPM·at block #6,792,649 · updates every 60s
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