Block #452,058

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/20/2014, 8:35:08 AM · Difficulty 10.3852 · 6,339,097 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
ef12c3120a243e58723e88d30f6dcf2a05f00777b75b778ba7993bcd2878dc01

Height

#452,058

Difficulty

10.385158

Transactions

3

Size

5.78 KB

Version

2

Bits

0a6299bf

Nonce

19,477,459

Timestamp

3/20/2014, 8:35:08 AM

Confirmations

6,339,097

Merkle Root

44116cc054ac431387200cbda15b74ae58961a4a598630d7c0920673dd07cc26
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.

3.952 × 10⁹⁷(98-digit number)
39520530851087422103…16826950347199060261
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
3.952 × 10⁹⁷(98-digit number)
39520530851087422103…16826950347199060261
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
7.904 × 10⁹⁷(98-digit number)
79041061702174844206…33653900694398120521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.580 × 10⁹⁸(99-digit number)
15808212340434968841…67307801388796241041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.161 × 10⁹⁸(99-digit number)
31616424680869937682…34615602777592482081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.323 × 10⁹⁸(99-digit number)
63232849361739875365…69231205555184964161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.264 × 10⁹⁹(100-digit number)
12646569872347975073…38462411110369928321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.529 × 10⁹⁹(100-digit number)
25293139744695950146…76924822220739856641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.058 × 10⁹⁹(100-digit number)
50586279489391900292…53849644441479713281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.011 × 10¹⁰⁰(101-digit number)
10117255897878380058…07699288882959426561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.023 × 10¹⁰⁰(101-digit number)
20234511795756760116…15398577765918853121
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:57,573,179 XPM·at block #6,791,154 · updates every 60s
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