Block #462,679

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/27/2014, 2:21:58 PM · Difficulty 10.4159 · 6,341,518 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
f228907c4a1d504bcdab00240f6b9727c8ab823521367e12b8b156e1c2a385f8

Height

#462,679

Difficulty

10.415914

Transactions

6

Size

1.59 KB

Version

2

Bits

0a6a7959

Nonce

24,654,895

Timestamp

3/27/2014, 2:21:58 PM

Confirmations

6,341,518

Merkle Root

8a1a17a43ba51223d938aa35b993f42605e4f09230fe006dfc594b2aff42a357
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.

2.901 × 10⁹⁶(97-digit number)
29014982628269187725…14064802814588561921
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
2.901 × 10⁹⁶(97-digit number)
29014982628269187725…14064802814588561921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.802 × 10⁹⁶(97-digit number)
58029965256538375450…28129605629177123841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.160 × 10⁹⁷(98-digit number)
11605993051307675090…56259211258354247681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.321 × 10⁹⁷(98-digit number)
23211986102615350180…12518422516708495361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.642 × 10⁹⁷(98-digit number)
46423972205230700360…25036845033416990721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.284 × 10⁹⁷(98-digit number)
92847944410461400720…50073690066833981441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.856 × 10⁹⁸(99-digit number)
18569588882092280144…00147380133667962881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.713 × 10⁹⁸(99-digit number)
37139177764184560288…00294760267335925761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.427 × 10⁹⁸(99-digit number)
74278355528369120576…00589520534671851521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.485 × 10⁹⁹(100-digit number)
14855671105673824115…01179041069343703041
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,677,623 XPM·at block #6,804,196 · updates every 60s
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