Block #712,830

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 9/8/2014, 9:18:54 PM · Difficulty 10.9558 · 6,089,843 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4fa502de5cbe3e02394534c8acb324172ad7225fb4b5a81f5b3904b2c7ee6e96

Height

#712,830

Difficulty

10.955757

Transactions

2

Size

431 B

Version

2

Bits

0af4ac85

Nonce

522,904,247

Timestamp

9/8/2014, 9:18:54 PM

Confirmations

6,089,843

Merkle Root

6ad7639fe6d93d9b6dd15cc91c6ff076506d7ca3c35f82cd34871d3d5ecd3229
Transactions (2)
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.

9.821 × 10⁹⁴(95-digit number)
98213241790797167348…42818863212878199039
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
9.821 × 10⁹⁴(95-digit number)
98213241790797167348…42818863212878199039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.964 × 10⁹⁵(96-digit number)
19642648358159433469…85637726425756398079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.928 × 10⁹⁵(96-digit number)
39285296716318866939…71275452851512796159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.857 × 10⁹⁵(96-digit number)
78570593432637733878…42550905703025592319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.571 × 10⁹⁶(97-digit number)
15714118686527546775…85101811406051184639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.142 × 10⁹⁶(97-digit number)
31428237373055093551…70203622812102369279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.285 × 10⁹⁶(97-digit number)
62856474746110187103…40407245624204738559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.257 × 10⁹⁷(98-digit number)
12571294949222037420…80814491248409477119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.514 × 10⁹⁷(98-digit number)
25142589898444074841…61628982496818954239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.028 × 10⁹⁷(98-digit number)
50285179796888149682…23257964993637908479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
1.005 × 10⁹⁸(99-digit number)
10057035959377629936…46515929987275816959
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 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
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,665,404 XPM·at block #6,802,672 · updates every 60s
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