Block #525,347

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/4/2014, 5:26:17 PM · Difficulty 10.8795 · 6,266,819 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8231f56a0bc66a408e16ce48fadb5072a93764f4c3b08549203454f9e90ac562

Height

#525,347

Difficulty

10.879467

Transactions

8

Size

2.62 KB

Version

2

Bits

0ae124c7

Nonce

118,200,549

Timestamp

5/4/2014, 5:26:17 PM

Confirmations

6,266,819

Merkle Root

2acbfab6ab15ad529a3f3b750b14a58cf7f7536847562d275173b73d59a4a9fd
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.

8.333 × 10¹⁰⁰(101-digit number)
83334867138123894588…42895383157034874879
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
8.333 × 10¹⁰⁰(101-digit number)
83334867138123894588…42895383157034874879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.666 × 10¹⁰¹(102-digit number)
16666973427624778917…85790766314069749759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.333 × 10¹⁰¹(102-digit number)
33333946855249557835…71581532628139499519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.666 × 10¹⁰¹(102-digit number)
66667893710499115670…43163065256278999039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.333 × 10¹⁰²(103-digit number)
13333578742099823134…86326130512557998079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.666 × 10¹⁰²(103-digit number)
26667157484199646268…72652261025115996159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.333 × 10¹⁰²(103-digit number)
53334314968399292536…45304522050231992319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.066 × 10¹⁰³(104-digit number)
10666862993679858507…90609044100463984639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.133 × 10¹⁰³(104-digit number)
21333725987359717014…81218088200927969279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.266 × 10¹⁰³(104-digit number)
42667451974719434029…62436176401855938559
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:57,581,283 XPM·at block #6,792,165 · updates every 60s
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