Block #346,898

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/6/2014, 8:09:52 PM · Difficulty 10.2358 · 6,458,268 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bd2e7a38c48a5eddff1edc73e807c060a5435f810933950894e5530f0104dd80

Height

#346,898

Difficulty

10.235806

Transactions

7

Size

1.95 KB

Version

2

Bits

0a3c5dca

Nonce

73,358

Timestamp

1/6/2014, 8:09:52 PM

Confirmations

6,458,268

Merkle Root

e9a4b42bab71ee534d5b2f592e4b03eece943d322194f11105254fa4b59a9e94
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.

5.965 × 10⁹⁸(99-digit number)
59654057258282280287…08477926769855871999
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
5.965 × 10⁹⁸(99-digit number)
59654057258282280287…08477926769855871999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.193 × 10⁹⁹(100-digit number)
11930811451656456057…16955853539711743999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.386 × 10⁹⁹(100-digit number)
23861622903312912114…33911707079423487999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.772 × 10⁹⁹(100-digit number)
47723245806625824229…67823414158846975999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.544 × 10⁹⁹(100-digit number)
95446491613251648459…35646828317693951999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.908 × 10¹⁰⁰(101-digit number)
19089298322650329691…71293656635387903999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.817 × 10¹⁰⁰(101-digit number)
38178596645300659383…42587313270775807999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.635 × 10¹⁰⁰(101-digit number)
76357193290601318767…85174626541551615999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.527 × 10¹⁰¹(102-digit number)
15271438658120263753…70349253083103231999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.054 × 10¹⁰¹(102-digit number)
30542877316240527507…40698506166206463999
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:57,685,396 XPM·at block #6,805,165 · updates every 60s
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