Block #575,083

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 6/3/2014, 6:04:43 PM · Difficulty 10.9680 · 6,219,325 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
e9c9b019fcb12435b4cd2f866a1d3dcbc97753ac725136abb6f47de5b988bc47

Height

#575,083

Difficulty

10.967963

Transactions

10

Size

2.18 KB

Version

2

Bits

0af7cc73

Nonce

601,154,487

Timestamp

6/3/2014, 6:04:43 PM

Confirmations

6,219,325

Merkle Root

dcb8c8075397eaebdf8c37303f32785947de79ec12b7c7196571602a03dc29c4
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.

6.049 × 10⁹⁸(99-digit number)
60497105504498186735…38612246952958378881
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
6.049 × 10⁹⁸(99-digit number)
60497105504498186735…38612246952958378881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.209 × 10⁹⁹(100-digit number)
12099421100899637347…77224493905916757761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.419 × 10⁹⁹(100-digit number)
24198842201799274694…54448987811833515521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.839 × 10⁹⁹(100-digit number)
48397684403598549388…08897975623667031041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
9.679 × 10⁹⁹(100-digit number)
96795368807197098777…17795951247334062081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.935 × 10¹⁰⁰(101-digit number)
19359073761439419755…35591902494668124161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.871 × 10¹⁰⁰(101-digit number)
38718147522878839510…71183804989336248321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
7.743 × 10¹⁰⁰(101-digit number)
77436295045757679021…42367609978672496641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.548 × 10¹⁰¹(102-digit number)
15487259009151535804…84735219957344993281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.097 × 10¹⁰¹(102-digit number)
30974518018303071608…69470439914689986561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
6.194 × 10¹⁰¹(102-digit number)
61949036036606143217…38940879829379973121
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:57,599,296 XPM·at block #6,794,407 · updates every 60s
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