Block #344,150

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 3:13:20 AM · Difficulty 10.1897 · 6,452,342 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9b656ebed74e442b5761c9f84251722f8458446f9b03c454faf2bccae6d65b26

Height

#344,150

Difficulty

10.189689

Transactions

7

Size

3.08 KB

Version

2

Bits

0a308f75

Nonce

58,924

Timestamp

1/5/2014, 3:13:20 AM

Confirmations

6,452,342

Merkle Root

0f5e502b2a155994846bbc7691bc2c28f21b21d27c6e04674f8b1f1cb8da06ad
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.

2.978 × 10¹⁰³(104-digit number)
29783086334344106401…07522829390954974359
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
2.978 × 10¹⁰³(104-digit number)
29783086334344106401…07522829390954974359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.956 × 10¹⁰³(104-digit number)
59566172668688212803…15045658781909948719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.191 × 10¹⁰⁴(105-digit number)
11913234533737642560…30091317563819897439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.382 × 10¹⁰⁴(105-digit number)
23826469067475285121…60182635127639794879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.765 × 10¹⁰⁴(105-digit number)
47652938134950570242…20365270255279589759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.530 × 10¹⁰⁴(105-digit number)
95305876269901140485…40730540510559179519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.906 × 10¹⁰⁵(106-digit number)
19061175253980228097…81461081021118359039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.812 × 10¹⁰⁵(106-digit number)
38122350507960456194…62922162042236718079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.624 × 10¹⁰⁵(106-digit number)
76244701015920912388…25844324084473436159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.524 × 10¹⁰⁶(107-digit number)
15248940203184182477…51688648168946872319
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:57,615,935 XPM·at block #6,796,491 · updates every 60s
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