Block #546,674

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/16/2014, 12:19:29 AM · Difficulty 10.9564 · 6,258,589 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
6d0bff236332a15b80b61ea0ca3661c1acb5bef06b9a1104a2b8f1db01131d50

Height

#546,674

Difficulty

10.956429

Transactions

9

Size

2.84 KB

Version

2

Bits

0af4d889

Nonce

7,713,578

Timestamp

5/16/2014, 12:19:29 AM

Confirmations

6,258,589

Merkle Root

95e09ebc07e5f63495f3dcddcf2bf3d61a1534fcaf652c5a2da77a44253e971a
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.

5.688 × 10⁹⁸(99-digit number)
56880599846931528753…22601066495892746241
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
5.688 × 10⁹⁸(99-digit number)
56880599846931528753…22601066495892746241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.137 × 10⁹⁹(100-digit number)
11376119969386305750…45202132991785492481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.275 × 10⁹⁹(100-digit number)
22752239938772611501…90404265983570984961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.550 × 10⁹⁹(100-digit number)
45504479877545223002…80808531967141969921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
9.100 × 10⁹⁹(100-digit number)
91008959755090446005…61617063934283939841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.820 × 10¹⁰⁰(101-digit number)
18201791951018089201…23234127868567879681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.640 × 10¹⁰⁰(101-digit number)
36403583902036178402…46468255737135759361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
7.280 × 10¹⁰⁰(101-digit number)
72807167804072356804…92936511474271518721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.456 × 10¹⁰¹(102-digit number)
14561433560814471360…85873022948543037441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.912 × 10¹⁰¹(102-digit number)
29122867121628942721…71746045897086074881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
5.824 × 10¹⁰¹(102-digit number)
58245734243257885443…43492091794172149761
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:57,686,174 XPM·at block #6,805,262 · updates every 60s
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