Block #483,756

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/10/2014, 5:35:19 AM · Difficulty 10.5691 · 6,320,441 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
01b30de3b985f497f78df90fe2312efe4e05a304876c96b639c79e2d8d1e6408

Height

#483,756

Difficulty

10.569052

Transactions

2

Size

1.02 KB

Version

2

Bits

0a91ad63

Nonce

32,146

Timestamp

4/10/2014, 5:35:19 AM

Confirmations

6,320,441

Merkle Root

dcea30d5590d29f803f83de43ed5f10de15d9eff58b59b39345397b31bab2d49
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.

1.016 × 10¹⁰⁰(101-digit number)
10167302873096087959…21362643843536802721
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
1.016 × 10¹⁰⁰(101-digit number)
10167302873096087959…21362643843536802721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.033 × 10¹⁰⁰(101-digit number)
20334605746192175918…42725287687073605441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.066 × 10¹⁰⁰(101-digit number)
40669211492384351837…85450575374147210881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.133 × 10¹⁰⁰(101-digit number)
81338422984768703674…70901150748294421761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.626 × 10¹⁰¹(102-digit number)
16267684596953740734…41802301496588843521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.253 × 10¹⁰¹(102-digit number)
32535369193907481469…83604602993177687041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.507 × 10¹⁰¹(102-digit number)
65070738387814962939…67209205986355374081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.301 × 10¹⁰²(103-digit number)
13014147677562992587…34418411972710748161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.602 × 10¹⁰²(103-digit number)
26028295355125985175…68836823945421496321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.205 × 10¹⁰²(103-digit number)
52056590710251970351…37673647890842992641
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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