Block #350,244

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/8/2014, 10:05:41 PM · Difficulty 10.2884 · 6,453,513 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b4d443c7f6fb5fae0cae15177571fe36f7509b6a8c1f962561b4a284ddcbbac5

Height

#350,244

Difficulty

10.288368

Transactions

17

Size

4.73 KB

Version

2

Bits

0a49d27b

Nonce

42,270

Timestamp

1/8/2014, 10:05:41 PM

Confirmations

6,453,513

Merkle Root

14ca39cb4cb3847b2c46d6ce13fccb04527f5322f8146480759218b064186327
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.

2.295 × 10¹⁰²(103-digit number)
22956351060360272494…72959764783087174399
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
2.295 × 10¹⁰²(103-digit number)
22956351060360272494…72959764783087174399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.591 × 10¹⁰²(103-digit number)
45912702120720544988…45919529566174348799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.182 × 10¹⁰²(103-digit number)
91825404241441089977…91839059132348697599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.836 × 10¹⁰³(104-digit number)
18365080848288217995…83678118264697395199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.673 × 10¹⁰³(104-digit number)
36730161696576435991…67356236529394790399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.346 × 10¹⁰³(104-digit number)
73460323393152871982…34712473058789580799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.469 × 10¹⁰⁴(105-digit number)
14692064678630574396…69424946117579161599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.938 × 10¹⁰⁴(105-digit number)
29384129357261148792…38849892235158323199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.876 × 10¹⁰⁴(105-digit number)
58768258714522297585…77699784470316646399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.175 × 10¹⁰⁵(106-digit number)
11753651742904459517…55399568940633292799
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:57,674,096 XPM·at block #6,803,756 · updates every 60s
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