Block #546,327

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 5/15/2014, 7:46:41 PM · Difficulty 10.9558 · 6,257,215 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
c9af675a895e579daf7f9db9662627d2972451d38877a62fd9a469851258ffbf

Height

#546,327

Difficulty

10.955760

Transactions

12

Size

3.06 KB

Version

2

Bits

0af4aca8

Nonce

278,464,230

Timestamp

5/15/2014, 7:46:41 PM

Confirmations

6,257,215

Merkle Root

038bbce2f5f1f037eea1e7576154edf769688902b075ad8da7814d1590226308
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.

3.642 × 10⁹⁸(99-digit number)
36425636373654089206…95756819619956981241
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
3.642 × 10⁹⁸(99-digit number)
36425636373654089206…95756819619956981241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
7.285 × 10⁹⁸(99-digit number)
72851272747308178412…91513639239913962481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.457 × 10⁹⁹(100-digit number)
14570254549461635682…83027278479827924961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.914 × 10⁹⁹(100-digit number)
29140509098923271364…66054556959655849921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.828 × 10⁹⁹(100-digit number)
58281018197846542729…32109113919311699841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.165 × 10¹⁰⁰(101-digit number)
11656203639569308545…64218227838623399681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.331 × 10¹⁰⁰(101-digit number)
23312407279138617091…28436455677246799361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.662 × 10¹⁰⁰(101-digit number)
46624814558277234183…56872911354493598721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
9.324 × 10¹⁰⁰(101-digit number)
93249629116554468367…13745822708987197441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.864 × 10¹⁰¹(102-digit number)
18649925823310893673…27491645417974394881
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:57,672,366 XPM·at block #6,803,541 · updates every 60s
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