Block #539,093

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/12/2014, 2:25:19 PM · Difficulty 10.9257 · 6,257,536 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
158ac1250e81c5dcc441d9992e27df1a7e426cf0a57ef8c418855e53eacc1047

Height

#539,093

Difficulty

10.925713

Transactions

9

Size

2.23 KB

Version

2

Bits

0aecfb8e

Nonce

446,693,598

Timestamp

5/12/2014, 2:25:19 PM

Confirmations

6,257,536

Merkle Root

41dddc27feb52111325910297b133a5c6919957f2ada6152752c24636f550647
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.

1.619 × 10¹⁰⁰(101-digit number)
16198900242071610964…00438961250422748161
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
1.619 × 10¹⁰⁰(101-digit number)
16198900242071610964…00438961250422748161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
3.239 × 10¹⁰⁰(101-digit number)
32397800484143221928…00877922500845496321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
6.479 × 10¹⁰⁰(101-digit number)
64795600968286443856…01755845001690992641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.295 × 10¹⁰¹(102-digit number)
12959120193657288771…03511690003381985281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.591 × 10¹⁰¹(102-digit number)
25918240387314577542…07023380006763970561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
5.183 × 10¹⁰¹(102-digit number)
51836480774629155084…14046760013527941121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.036 × 10¹⁰²(103-digit number)
10367296154925831016…28093520027055882241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.073 × 10¹⁰²(103-digit number)
20734592309851662033…56187040054111764481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
4.146 × 10¹⁰²(103-digit number)
41469184619703324067…12374080108223528961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
8.293 × 10¹⁰²(103-digit number)
82938369239406648135…24748160216447057921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.658 × 10¹⁰³(104-digit number)
16587673847881329627…49496320432894115841
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,617,032 XPM·at block #6,796,628 · updates every 60s
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