1. #6,799,3131CC11 primes

    Cunningham 1st · ⛏️ coinsforall.io

Block #382,543

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/30/2014, 6:59:00 PM · Difficulty 10.4034 · 6,416,771 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
6f7ea3a175633755e5c01fe1b5318e4e2653adad83931d45601108f4eec8142a

Height

#382,543

Difficulty

10.403402

Transactions

3

Size

1.51 KB

Version

2

Bits

0a67455f

Nonce

83,888,679

Timestamp

1/30/2014, 6:59:00 PM

Confirmations

6,416,771

Merkle Root

5f1b57dce98789ecb26cf7dffdd975c1d5475a7e697fca0041d5b43e8e4cbe20
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.

1.501 × 10⁹⁶(97-digit number)
15018346577771158634…88345812951840649921
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
1.501 × 10⁹⁶(97-digit number)
15018346577771158634…88345812951840649921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
3.003 × 10⁹⁶(97-digit number)
30036693155542317268…76691625903681299841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
6.007 × 10⁹⁶(97-digit number)
60073386311084634536…53383251807362599681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.201 × 10⁹⁷(98-digit number)
12014677262216926907…06766503614725199361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.402 × 10⁹⁷(98-digit number)
24029354524433853814…13533007229450398721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.805 × 10⁹⁷(98-digit number)
48058709048867707629…27066014458900797441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
9.611 × 10⁹⁷(98-digit number)
96117418097735415258…54132028917801594881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.922 × 10⁹⁸(99-digit number)
19223483619547083051…08264057835603189761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.844 × 10⁹⁸(99-digit number)
38446967239094166103…16528115671206379521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.689 × 10⁹⁸(99-digit number)
76893934478188332206…33056231342412759041
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:57,638,559 XPM·at block #6,799,313 · updates every 60s
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