Block #526,683

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/5/2014, 1:18:53 PM · Difficulty 10.8830 · 6,276,595 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
243cd869d73b1e0ebc7c6a8424471a7e67359c2074f6766e72193dd5ff11b054

Height

#526,683

Difficulty

10.882965

Transactions

8

Size

2.22 KB

Version

2

Bits

0ae209fc

Nonce

75,377

Timestamp

5/5/2014, 1:18:53 PM

Confirmations

6,276,595

Merkle Root

3d336adcd956ac0248dec8eb066bda9806e40ea0c01dd0d679e52022cc116cef
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.

4.902 × 10⁹⁵(96-digit number)
49029876923599670957…93500933433205951999
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
4.902 × 10⁹⁵(96-digit number)
49029876923599670957…93500933433205951999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.805 × 10⁹⁵(96-digit number)
98059753847199341915…87001866866411903999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.961 × 10⁹⁶(97-digit number)
19611950769439868383…74003733732823807999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.922 × 10⁹⁶(97-digit number)
39223901538879736766…48007467465647615999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.844 × 10⁹⁶(97-digit number)
78447803077759473532…96014934931295231999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.568 × 10⁹⁷(98-digit number)
15689560615551894706…92029869862590463999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.137 × 10⁹⁷(98-digit number)
31379121231103789412…84059739725180927999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.275 × 10⁹⁷(98-digit number)
62758242462207578825…68119479450361855999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.255 × 10⁹⁸(99-digit number)
12551648492441515765…36238958900723711999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.510 × 10⁹⁸(99-digit number)
25103296984883031530…72477917801447423999
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,670,250 XPM·at block #6,803,277 · updates every 60s
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